If (-1, -1) is an extremum of [tex]f[/tex], then both partial derivatives vanish at this point.
Compute the gradients and evaluate them at the given point.
[tex]f(x,y)=xy+\frac1x +\frac1y[/tex][tex]\nabla f = \left\langle y - \dfrac1{x^2}, x - \dfrac1{y^2}\right\rangle \implies \nabla f (-1,-1) = \langle-2,-2\rangle \neq \langle0,0,\rangle[/tex]
[tex]f(x,y) = x^2+2x[/tex][tex]\nabla f = \langle 2x+2,0\rangle \implies \nabla f(-1,-1) = \langle0,0\rangle[/tex]
[tex]f(x,y)=xy-y^2[/tex][tex]\nabla f = \langle y, x-2y\rangle \implies \nabla f(-1,1) = \langle-1,1\rangle \neq\langle0,0\rangle[/tex]
[tex]f(x,y) = xy-\frac1x-\frac1y[/tex][tex]\nabla f = \left\langle y + \frac1{x^2}, x + \frac1{y^2}\right\rangle \implies \nabla f(-1,1) = \langle0,0\rangle[/tex]
The first and third functions drop out.
The second function depends only on [tex]x[/tex]. Compute the second derivative and evaluate it at the critical point [tex]x=-1[/tex].
[tex]f(x,y) = x^2+2x \implies f'(x) = 2x + 2 \implies f''(x) = 2 > 0[/tex]
This indicates a minimum when [tex]x=-1[/tex]. In fact, since this function is independent of [tex]y[/tex], every point with this [tex]x[/tex] coordinate is a minimum. However,
[tex]x^2 + 2x = (x + 1)^2 - 1 \ge -1[/tex]
for all [tex]x[/tex], so (-1, 1) and all the other points [tex](-1,y)[/tex] are actually global minima.
For the fourth function, check the sign of the Hessian determinant at (-1, 1).
[tex]H(x,y) = \begin{bmatrix} f_{xx} & f_{xy} \\ f_{yx} & f_{yy} \end{bmatrix} = \begin{bmatrix} -2/x^3 & 1 \\ 1 & -2/y^3 \end{bmatrix} \implies \det H(-1,-1) = 3 > 0[/tex]
The second derivative with respect to [tex]x[/tex] is -2/(-1) = 2 > 0, so (-1, -1) is indeed a local minimum.
The correct choice is the fourth function.
6. (a) In the given figure, AD and BC are two straight lines. If ZBAO = 50°, ZABO = 60° and ZPCD = 130° then find the values of x and y. 50 60% B 130
Answer: 70 and 60 degrees
Step-by-step explanation:
Angle AOB = 180 - 50 - 60 = 70 degrees so x is 70 degrees
Angle OCD = 180 - 130 = 50 so y = 180 - 70 - 50 = 60 degrees
A bagel factory produced 300 bags of bagels. There were 7 bagels in each bag. How many
bagels did the factory produce?
bagels
A regular octagon has side lengths of 8 centimeters. What is the approximate area of the octagon?
Answer:
The answer is B if the octagon has side lengths of 8
Open Ended
a. Find the slope of the line that passes through the points (2,-5) and (-2,3).
b. What are the slope and y-intercept of the equation 2x - 5y = -10?
c. Find the x value so that the line through the points (x,-9) and (0,1) has a slope of -4.
d. Write the equation of a line that passes through the point (-1,5) and has a slope of -7. Your answer should be given in the form y = mx + b.
(PLEASE SHOW WORK, IT CAN BE SIMPLE I JUST NEED TO PUT IT IN FOR CREDIT)
a.
Solution Given:
Slope of the line passing through the point is
m= [tex] \frac{y_2-y_1}{x_2-x_1}=\frac{3-(-5)}{-2-2}=\frac{8}{-4}=-2[/tex]
slope=-2
b.
Solution given:
equation is
2x-5y=-10
2x+10=5y
y=2x/5 +10/5
y=2/5 x +3
comparing above equation with y=mx+c
we get
m=2/5
slope=2/5
c.
Slope of the line passing through the point is
m=[tex] \frac{y_2-y_1}{x_2-x_1}[/tex]
-4=[tex] \frac{1-(-9)}{0-x}[/tex]
-4=10/-x
doing criss cross multiplication
-4*-x=10
4x=10
x=10/4
x=5/2
slope=5/2
d.
we have
equation of line passing through the one point is
[tex] y-y_1=m(x-x_1)[/tex]
y-5=-7(x-(-1))
y=-7(x+1)+5
y=-7x-7+5
y=-7x-2 is a required equation:
In two or more complete sentences write and solve an equation for the situation and explain how you will solve the equation. Fifty students were given a pre and post test for their math course. Overall, most students increased their scores by 20% points. The grades on the post test went up to 95%. What is the starting range for the grades on the test?
We conclude that the starting average grade is 79.17%
How to write the equation and solve it?There are 50 students, let's say that the grades are measured between 1% and 100%.
And the average grade of the 50 students is A.
We know that after it increased by 20%, the average of the grades is 95.
Then we just need to solve the percentage equation:
95 = A*(1 + 20%/100%) = A*(1.2)
95/1.2 = A = 79.17
We conclude that the starting average grade is 79.17%
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Answer:
75%
Step-by-step explanation:
You need to do the following equation: x+20≤95 and you will have the answer. (I am sorry if it is wrong but this is what my teacher told the answer was. I put this answer and got it correct.) Hope it helped. Have a nice day.
Remy obtains a 30-year mortgage in the amount of $625,000 for a co-op. She secures a 7/1 ARM at an initial interest rate of 3%. Her initial monthly payment is $2,635.03. After 7 years, the interest rate on her loan changes to 4.925%. Calculate her new monthly payment in year 8 of the loan. (Round your answer to the nearest cent.)
The new monthly payment is $3,181.53
What is ARM?
ARM stands adjustable rate mortgage, which means that the interest rate applicable to the mortgage would change during the life of the mortgage, in this case, 7/1 ARM means that interest rate of 3% is applicable for the first 7 years and the rate would change in year 8 to another interest rate, which is 4.925% as hinted at in the question.
To determine the monthly payment in year 8 , we need to compute the outstanding balance at the end of year 7, which is the opening balance in year 8 using the present value formula of an ordinary annuity since monthly payments would occur at the end of each month
PV(balance at the end of year 7)=PMT*(1-(1+r)^-N/r
PMT=initial monthly payment=$2,635.03
r=initial monthly interest rate=3%/12=0.0025
N=number of monthly payments in the remaining 23 years(i.e 30-7)=23*12
N=number of monthly payments in the remaining 23 years(i.e 30-7)=276
PV=$2,635.03*(1-(1+0.0025)^-276/0.0025
PV=$2,635.03*(1-0.502008144755209)/0.0025
PV=$2,635.03*0.497991855244791/0.0025
PV=$ 524,889.39
With the balance at the end of year 7, we can now compute monthly payment in year 8 using the same formula as above where the unknown is the PMT, PV=$ 524,889.39 and r= 4.925%.
$524,889.39=PMT*(1-(1+4.925%/12)^-276/4.925%/12)
$524,889.39=PMT*(1-(1.00410416666666667
)^-276/0.00410416666666667
$524,889.39=PMT*(1-0.32289378683267300
)/0.00410416666666667
$524,889.39=PMT*164.98019407122700000
PMT=$524,889.39/164.98019407122700000
PMT=$3,181.53
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If u spend $25 per day. How many days will it take you to spend $1,000
Answer:
4days atlases in the week
Quantity day
25------------------1
1000---------------x
We solve
[tex]\boldsymbol{\sf{x=\dfrac{1000\times1}{25}=\dfrac{1000}{25}=40 }}[/tex]
Answer: To spend $1,000 it will take 40 days.
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Simplify the expression cos (tan-1(x/2)).
\cos (\tan \left( -1\right) (\frac{x}{2}))
c
o
s
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t
a
n
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−
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2
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Simplify
1
Combine multiplied terms into a single fraction
\cos (\tan \left( -1\right) \cdot \frac{x}{2})
c
o
s
(
t
a
n
(
−
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)
⋅
2
)
\cos (\frac{\tan \left( -1\right) x}{2})
c
o
s
(
t
a
n
(
−
1
)
2
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Solution
\cos \left( \frac{\tan \left( -1\right) x}{2}\right)
c
o
s
(
t
a
n
(
−
1
)
2
)
Answer:
Step-by-step explanation:
[tex]cos(tan^{-1}(\frac{x}{2} ))\\put~tan^{-1}(\frac{x}{2} )=t\\\frac{x}{2} =tan~t\\sec^2t-tan^2t=1\\sec^2t=1+tan^2t=1+(\frac{x}{2} )^2=\frac{x^2+4}{4} \\sec~t=\pm\frac{\sqrt{x^2+4}}{2} \\cos ~t=\pm\frac{2}{\sqrt{x^2+4}} \\hence~cos(tan^{-1}(\frac{x}{2} ))=cos~t=\pm\frac{2}{\sqrt{x^2+4}}[/tex]
what is (x+6) (x+6) expanded
Hello and Good Morning/Afternoon:
Let's take this problem step-by-step:
When we expand a function, everything must be multiplied out evenly.
[tex](x+6)*(x+6)\\=x*x +x*6+6*x+6*6\\=x^2 + 6x + 6x+36\\x^2 +12x+36[/tex]
Answer: x² + 12x + 36
Hope that helps!
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Polynomials are mathematical expressions made up of many terms.
To simplify the polynomial to the maximum, all like terms must be grouped together and rearranged from highest to lowest power.
(x + 6)(x + 6)Distribute
x(x + 6) + 6(x + 6)x² + 6x + 6(x + 6)x² + 6x + 6x + 36Combining like terms.
x² + 12x + 36See more in:https://brainly.com/question/28184428A container manufacturer plans to make rectangular boxes whose bottom and top measure x by 4x. The container must contain 8cm3. The top and the bottom will cost $3.90 per square centimeter, while the four sides will cost $4.90 per square centimeter.
What should the height of the container be so as to minimize cost? Round your answer to the nearest hundredth.
The most efficient measurements of the box should be 4cm long, 1cm wide and 2cm high so that its cost is $129.2
How to calculate the measures of the rectangular box?To calculate the measurements of the rectangular box we must take into account the following condition:
Bottom and top measure x by 4x.According to the above, we can establish that the most appropriate measurement for the bottom and top should be 1cm (width) × 4cm (length). Additionally we can establish that the height of the box would be 2cm.
How to find the volume of this box?To find the volume of the box we must use the following formula:
height × width × length = volume.2cm × 1cm × 4cm = 8cm³What are the areas of this box?The areas of this box are:
Bottom and top: 1cm × 4cm = 4cm²Sides: 1cm × 2cm = 2cm²Front and rear: 2cm × 4cm² = 8cm²What is the price of this box?The total price of this box is as follows:
Top and bottom:
4cm² × $3.90 = $15.6$15.6 × 2 = $31.2Sides:
2cm² × $4.90 = $9.80$9.80 × 2 = $19.68cm² × $4.90 = $39.2$39.2 × 2 = $78.4$78.4 + $19.6 + $31.2 = $129.2Learn more about boxes in: https://brainly.com/question/23952628
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A two digit number has 6 more ones than tens. Twice the sum of the number and its reverse is 6 more than ten times the number. Find the number.
The number with the given properties is 17
How to determine the numbers?Let the tens be x and the units be y.
So, the number is 10x + y
The relationship between the digits is
[tex]y = x + 6[/tex]
The relationship between the number and the reverse is
[tex]2(10x + y + 10y + x) = 6 + 10 * (10x + y)[/tex]
Simplify the second equation
[tex]2(11x + 11y) = 6 + 100x + 10y[/tex]
Open the brackets
[tex]22x + 22y = 6 + 100x + 10y[/tex]
Substitute y = x + 6
[tex]22x + 22(x + 6) = 6 + 100x + 10(x + 6)[/tex]
Expand
[tex]22x + 22x + 132 = 6 + 100x + 10x + 60[/tex]
Collect like terms
[tex]22x + 22x - 100x - 10x = 6 + 60 - 132[/tex]
Evaluate the like terms
[tex]-66x = -66[/tex]
Divide by -66
x = 1
Substitute x = 1 in y = x + 6
[tex]y = 1 + 6[/tex]
y = 7
Recall that the number is 10x + y
So, we have
Number = 10 * 1 + 7
Evaluate
Number = 17
Hence, the number is 17
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The first five terms of a quadratic sequence are 3, 12, 25, 42, 63.
Find the nth term of this sequence.
Since we know the sequence is quadratic, we expect the [tex]n[/tex]-th term to have the general form
[tex]x_n = an^2 + bn + c[/tex]
Plug in the first 3 known values of the sequence to form a system of equations.
[tex]x_1 = 3 = a + b + c[/tex]
[tex]x_2 = 12 = 4a + 2b + c[/tex]
[tex]x_3 = 25 = 9a + 3b + c[/tex]
Eliminating [tex]c[/tex] gives
[tex](4a + 2b + c) - (a + b + c) = 12 - 3 \implies 3a + b = 9[/tex]
[tex](9a + 3b + c) - (a + b + c) = 25 - 3 \implies 8a + 2b = 22 \implies 4a + b = 11[/tex]
Eliminating [tex]b[/tex] gives
[tex](4a + b) - (3a + b) = 11 - 9 \implies a = 2[/tex]
Solving for [tex]b,c[/tex], we get
[tex]4a + b = 11 \implies b = 11-4\cdot2 = 3[/tex]
[tex]a+b+c=3 \implies c=3-2-3 = -2[/tex]
So, the [tex]n[/tex]-th term of the sequence is
[tex]x_n = \boxed{2n^2 + 3n - 2}[/tex]
the sum of three consecutive integers is 78. what are the three Integers
Answer:
25, 26, and 27 are the three consecutive integers.
Step-by-step explanation:
Let the numbers be represented as x, x + 1 and x + 2.
We can write the equation:
[tex]x+(x+1)+ (x+2)=78[/tex]
Opening the brackets and simplifying:
[tex]x+x+1+x+2=78[/tex]
[tex]3x+3=78[/tex]
Subtract 3 from both sides.
[tex]3x=75[/tex]
Divide both sides by 3.
[tex]x=25[/tex]
Since the three consecutive integers are x, x + 1 and x + 2, replace x with 25.
∴ 25, 26 and 27 are the three consecutive integers.
Answer:
25 , 26 and 27
Step-by-step explanation:
Patty pays $235 in advance on her account at the athletic club. Each time she uses the club, $6 is deducted from the account. Write an equation that represents the value remaining in her account after x visits to the club. Find the value remaining in the account after 5 visits.
a. V=235 - 6x; $1415
b. V= 6 - 235x; $205
c. V=235 - 6x; $1401
d. V=235 - 6x; $205
*show your work*
Answer:
205
Step-by-step explanation:
We start with 235, this will be our y-intercept.
6 Is deducted from our value every visit, making our slope -6.
Put the two into slope intercept form:
[tex]y=235-6x[/tex]
To find the value after 5 visits substitute x for 5:
[tex]y=235-6(5)[/tex]
Solve
[tex]y=235-6(5)\\y=235-30\\y=205[/tex]
Therefore you have 205 left in your account after 5 visits.
Instructions: Identify the vertices of the feasible region and use them to find the maximum and/or minimum value for the given linear programming constraints.
System of Linear Programming:
z=−3x+5y
x+y≥−22
x−y≥−4
x−y≤2
Minimum value of z:
The minimum value of z is -38
How to identify the vertices of the feasible region for the given linear programming constraints?The optimization equation is given as
z=−3x+5y
The constraints are given as:
x+y≥−2
3x−y≤2
x−y≥−4
Next, we plot the constraints on a graph and determine the points of intersections
See attachment for the graph
From the attached graph, the points of intersections are
(-9, -13) and (-10, -12)
So, we have:
(-9, -13)
(-10, -12)
Substitute these values in the objective function
z=−3x+5y
This gives
z= −3 * -9 +5 * -13 = -38
z= −3 * -10 +5 * -12 = -30
-38 is less than -30
Hence, the minimum value of z is -38
So, the complete parameters are:
Optimization Equation:
z=−3x+5y
Constraints:
x+y≥−2
3x−y≤2
x−y≥−4
Vertices of the feasible region
(0, -2)
(-3, 1)
(3, 7)
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Given: m space measured angle space B equals 18 degree, b = 9, and c = 20. Find m space measured angle space C degree to nearest whole number.
Given the measure of angle B, side b and side, the measure of angle C to the nearest whole number is 43 degrees.
What is the measure of angle space C?
From the Rule of Sine;
sinA/a = sinB/b = sinC/c
Where A,B and C are the angles of the triangle and a, b and c are the corresponding opposing sides.
Given that;
Angle B = 18°side b = 9side c = 20Angle C = ?Using the rule of sine.
sinB/b = sinC/c
We substitute the given values into the equation
sin( 18° )/9 = sinC/20
We solve for C.
sin( 18° ) × 20 = sinC × 9
0.309016994 × 20 = sinC × 9
6.18033988 = sinC × 9
Divide both sides by 9
6.18033988/9 = (sinC × 9)/9
sinC = 0.686704431
C = sin⁻¹( 0.686704431 )
C = 43.3697°
C = 43°
Given the measure of angle B, side b and side, the measure of angle C to the nearest whole number is 43 degrees.
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THE NICHOLS ARE BUYING A HOUSE SELLING FOR $245,000. THEY PAY A DOWN
PAYMENT OF $45,000 FROM THE SALE OF THEIR CURRENT HOUSE. TO OBTAIN A 15-
YEAR MORTGAGE AT 4.5% INTEREST, THEY MUST PAY 1.5 POINTS AT THE TIME OF
CLOSING. WHAT IS THE AMOUNT OF THE MORTGAGE, AND WHAT IS THE COST OF
THE 1.5 POINTS
The amount of the mortgage on this house is given as $300000, while the 1.5 points on the house is given as 3000 dollars
How to solve for the mortgage that is on this houseThe data from the questions says that the cost of the house = $245000
The down payment amount amount is 45000
Given that they already paid 45000 from the cost of the house, the mortgage would be 245000 - 45000
= $200000
The cost of 1.5 points is the same as the cost of 1.5% of the mortgage of this house.
This is calculated as 0.015 x 200000
= $3000
The conclusion is that the amount of the mortgage on this house is given as $300000, while the 1.5 points on the house is given as 3000 dollars
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Questions are in the picture
The closest point is (3.5, 1.9) and the distance is 1.96 units
How to determine the point and the distance?The coordinate is given as:
(4, 0)
The equation of the function is
y = √x
The distance between two points is calculated using
d = √(x2 - x1)^2 + (y2 - y1)^2
So, we have the following points
(x1, y1) = (4, 0) and (x2, y2) = (x, 0)
This gives
d = √(x - 4)^2 + (√x - 0)^2
Evaluate the difference
d = √(x - 4)^2 + (√x)^2
Evaluate the exponent
d = √x^2 - 8x + 16 + x
Evaluate the like terms
d = √x^2 - 7x + 16
Next, we differentiate using a graphing calculator
d' = (2x - 7)/[2√(x^2 - 7x + 16)]
Set to 0
(2x - 7)/[2√(x^2 - 7x + 16)] = 0
Cross multiply
2x - 7 = 0
Add 7 to both sides
2x = 7
Divide by 2
x = 3.5
So, we have:
Substitute x = 3.5 in y = √x
y = √3.5
Evaluate
y = 1.9
So, the point is (3.5, 1.9)
The distance is then calculated as:
d = √(x2 - x1)^2 + (y2 - y1)^2
This gives
d = √(3.5 - 4)^2 + (1.9 - 0)^2
Evaluate
d = 1.96
Hence, the closest point is (3.5, 1.9) and the distance is 1.96 units
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A COUPLE PLAN TO HAVE THREE CHILDREN.
A) LIST ALL THE POSSIBILITIES FOR THE SAMPLE SPACE.
B) WHAT IS THE PROBABILITY THAT THEY HAVE AT MOST TWO BOYS?
C) WHAT IS THE PROBABILITY THAT THEY HAVE AT LEAST TWO GIRLS?
D) WHAT IS THE PROBABILITY THAT THEY ARE ALL OF THE SAME SEX?
Using the sample space and probability concepts, we have that:
A) All the possibilities for the sample space are: {{G,G,G}, {G,G,B}, {G,B,G}, {G,B,B}, {B,G,G}, {B,G,B}, {B,B,G}, {B,B,B}}.
B) The probability is: 7/8.
C) The probability is: 1/2.
D) The probability is: 1/4.
What is a probability?A probability is given by the number of desired outcomes divided by the number of total outcomes.
The sample space is the set that contains all possible outcomes, hence in this problem, considering G for girl and B for boy, it is given by:
{{G,G,G}, {G,G,B}, {G,B,G}, {G,B,B}, {B,G,G}, {B,G,B}, {B,B,G}, {B,B,B}}.
For item B, 7 outcomes have at most two boys, hence the probability is 7/8.
For item C, 4 outcomes have at least two girls, hence the probability is 4/8 = 1/2.
For item D, 2 outcomes have all the babies with the same sex, hence the probability is 2/8 = 1/4.
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simply the following expression by combining like terms 5w + 7v - 8w + v - w + 2y
Find the value of c.
answer choices
A. 26
B. 104
C. 52
D. 93.5
Answer:
option B is the answer of given question
Answer:
D. 93.5
Step-by-step explanation:
Angle Formed by Two Chords= 1/2(SUM of Intercepted Arcs)
The lower arc is twice 52
c = 1/2( 104 +83)
c = 1/2 ( 187)
c =93.5
please help urgently
Solving for y:
6y - 2x = 20
6y = 2x + 20
y = [tex]\frac{2x + 20}{6}[/tex]
y = [tex]\frac{2x}{6} + \frac{20}{6}[/tex]
y = [tex]\frac{1x}{3} + \frac{10}{3}[/tex]
Hope it helps!
Answer:
Step-by-step explanation:
6y - 2x = 20
-6 -6
-2x = 20 - 6y
divide both sides by -2
[tex]\frac{-2x}{-2}[/tex] = [tex]\frac{20 - 6y}{-2}[/tex]
Dividing by -2 undoes the multiplication by -2.
[tex]x = \frac{20 - 6y}{ -2}[/tex]
Divide 20 -6 by -2
x = 3y - 10
Or
y = [tex]\frac{10}{3}[/tex]x +[tex]\frac{x}{3}[/tex]
HELPP PLSSS I NEED HELP!!!
Answer:
(3+3) x (3+1)
Step-by-step explanation:
free
We have give 4 numbers that are 1,3,3,3. we have to apply operations on it to make it 24.
Solution :» (1 + 3) × (3 + 3)
» (4) × (6)
» 24
Here's our answer..!!
Use the graph to determine a. the function's domain; b. the function's range; c. the
x-intercepts, if any; d. the y-intercept, if there is one; e. the following function
values.
f(-3)
f(0)
7-8-5-4-3-2-1
Q
2
Part a
The domain is the set of x-values, which is [tex](-\infty, \infty)[/tex]
Part b
The range is the set of y-values, which is [tex](-\infty, -2][/tex]
Part c
The x-intercepts is when y=0, which there are none of.
Part d
The y-intercept is when x=0, which is at (0, -2).
Si al invertir $60.000 se pierde un 8% ¿A cuánto asciende la pérdida?
Trabajando con porcentajes, concluimos que la pérdida es de $4800.
¿A cuánto asciende la pérdida?
Sabemos que la inversión inicial es de $60000, y de esta cantidad, se pierde un 8%.
Entonces la pérdida va a ser el 8% de $60000.
Podemos escribir las relaciones:
$60000 = 100%
x = 8%
Queremos resolver esto para x, tomando el cociente entre esas relaciones y resolviendo para x obtenemos:
x = $60000*(8%/100%) = $60000*0.08 = $4800
Así, concluimos que la pérdida es de $4800.
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value of 10 in A/B
value of letter
The value of the expression (a - b)² from the given equations is; 16
How to solve simultaneous equations?
We are given the two equations as;
a + b = 10 -----(eq 1)
ab = 21 ------(eq 2)
From eq 1, square both sides;
(a + b)² = 10²
a² + 2ab + b² = 100
a² + b² = 100 - 2ab
We are given ab = 21. Thus;
a² + b² = 100 - 2(21)
a² + b² = 58
Now, we know that (a - b)² = a² - 2ab + b²
Thus;
(a - b)² = 58 - 2(21)
(a - b)² = 16
Complete question is;
If a + b = 10 and ab = 21, then the value of (a - b)² is?
Read more about Simultaneous equations at; https://brainly.com/question/148035
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Ritchie got a job at the movie theater. On the first day, he sold 5 adult tickets and 7 children tickets for a total of 104. On the second day he sold 7 adult tickets and 3 children tickets for a total of 98. What is the price for each ticket?
Answer:
A = $11; C = $7 tickets
Step-by-step explanation:
Using the given info, we can create a system of equations to find the price of adult and children tickets.
Thus, we have 5A + 7C = 104 and 7A + 3C = 98
The easiest method to solve would be elimination:
Answer:
adult: $11children: $7Step-by-step explanation:
The sales on the two days can be expressed using equations that can be solved for ticket prices.
SetupLet x and y represent the prices of adult and children's tickets, respectively. Then the sales revenue for the two days can be expressed in the equations ...
5x +7y = 1047x +3y = 98SolutionOne of the easiest solution methods is to use a graphing calculator. The first attachment shows the prices are $11 for an adult ticket; $7 for children tickets.
Using the matrix functions of a calculator, the augmented matrix of the equation coefficients can be reduced to row-echelon form. This, too, shows the solution to be (adult price, children price) = ($11, $7). See the second attachment. (The solution is the right-most column of the reduced matrix.)
Yet another solution method can use the coefficients from the equations written in general form:
5x +7y -104 = 07x +3y -98 = 0In this form, we define three products of "cross multiplication":
Δ1 = (5)(3) -(7)(7) = -34
Δ2 = (7)(-98) -(3)(-104) = -374
Δ3 = (-104)(7) -(-98)(5) = -238
Using those, we find the variable values to be ...
x = Δ2/Δ1 = -374/-34 = 11
y = Δ3/Δ1 = -238/-34 = 7
(adult price, children price) = ($11, $7)
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You can read more about the cross-multiplication method here:
https://brainly.com/question/26397343
anna bought a sweater at 40% off the original price. if she paid $12 what was the original price of the sweater?
Answer:
The original price was $30
Step-by-step explanation:
40% = 40/100 = 0.4
[tex]\frac{12}{0.4} =30[/tex]
Hope this helps
g. Exactly 14 proper subsets h. Exactly 15 proper subsets How many elements does A contain if it h a. 64 subsets? b. 31 proper subsets? c. No proper subset? d. 255 proper subsets?
I don't know what you mean by g. and h., so I'll just skip that part.
I'm assuming you're asking about some arbitrary finite set [tex]A[/tex].
a. If [tex]A[/tex] has 64 subsets, then [tex]A[/tex] has [tex]\log_2(64) = \boxed{6}[/tex] elements. This is because a set of [tex]n[/tex] elements has [tex]2^n[/tex] subsets/elements in its power set.
b. A proper subset is a subset that doesn't contain all the elements of the parent set. This means we exclude the set [tex]A[/tex] from its power set. The power set itself would have 32 elements, so [tex]A[/tex] would have [tex]\log_2(32) = \boxed{5}[/tex] elements.
c. The empty set is a proper subset of any non-empty set. However, if [tex]A=\emptyset[/tex], then it has no proper subsets. So [tex]A[/tex] must be the empty set and have [tex]\boxed{0}[/tex] elements.
d. By the same reasoning as in part (b), if [tex]A[/tex] has 255 proper subsets, then it has a total of 256 subsets, and [tex]\log_2(256) = \boxed{8}[/tex].
Calculate the weight on earth of an object with a mass of 48kg
Answer: 470.4 N
Step-by-step explanation:
Concept:
1 kg on Earth = 9.8 N
Given information:
Mass = 48 kg
Find the weight on Earth
1 kg = 9.8 N
48 kg = 48 * 9.8 = [tex]\Large\boxed{470.4N\\}[/tex]
Hope this helps!! :)
Please let me know if you have any questions