Answer:
110 marbles
side 14
Step-by-step explanation:
Draw triangles using marbles as the sides.
If the side is 2 marbles long, the triangle uses 3 marbles. 1 + 2 = 3
If the side is 3 marbles long, the triangle uses 6 marbles. 1 + 2 + 3 = 6
If the side is 4 marbles long, the triangle uses 10 marbles. 1 + 2 + 3 + 4 = 10
If the side is n marbles long, the triangle uses n(n + 1)/2 marbles.
These numbers are called triangular numbers.
We are looking for the side, n.
n(n + 1)/2 + 5 = (n + 1)(n + 2)/2 - 10
n^2 + n + 10 = n^2 + 3n + 2 - 20
n + 10 = 3n - 18
-n = -14
n = 14
For n = 14
n(n + 1)/2 =
= 14(15)/2
= 105
For n = 15
n(n + 1)/2 =
= 15(16)/2
= 120
105 + 5 = 120 - 10
You have 110 marbles. If you had 5 fewer, 105, you'd have a triangle with sides 14. If you had 10 more, 120, you'd have a triangle with sides 15. Since you have 110, you have 5 too many for side 14 and 10 too few for side 15.
The sides of the triangle is 14.
If f(n) = 4n + 7 and g(n) = 2n + 3, find (g - f)(n).
2(n-4)
4- 2n
-2n - 4
2n + 4
Step-by-step explanation:
=(g-f)(n)
=4n+7-2n-3
=2n+4
which of the following are identities? check all that apply.
A. (sinx + cosx)^2= 1+sin2x
B. sin6x=2 sin3x cos3x
C. sin3x/sinxcosx = 4cosx - secx
D. sin3x-sinx/cos3x+cosx = tanx
Answer: (a), (b), (c), and (d)
Step-by-step explanation:
Check the options
[tex](a)\\\Rightarrow [\sin x+\cos x]^2=\sin ^2x+\cos ^2x+2\sin x\cos x\\\Rightarrow [\sin x+\cos x]^2=1+2\sin x\cos x\\\Rightarrow \Rightarrow [\sin x+\cos x]^2=1+\sin 2x[/tex]
[tex](b)\\\Rightarrow \sin (6x)=\sin 2(3x)\\\Rightarrow \sin 2(3x)=2\sin (3x)\cos (3x)[/tex]
[tex](c)\\\Rightarrow \dfrac{\sin 3x}{\sin x\cos x}=\dfrac{3\sin x-4\sin ^3x}{\sin x\cos x}\\\\\Rightarrow 3\sec x-4\sin ^2x\sec x\\\Rightarrow 3\sec x-4[1-\cos ^2x]\sec x\\\Rightarrow 3\sec x-4\sec x+4\cos x\\\Rightarrow 4\cos x-\sec x[/tex]
[tex](d)\\\Rightarrow \dfrac{\sin 3x-\sin x}{\cos 3x+\cos x}=\dfrac{2\cos [\frac{3x+x}{2}] \sin [\frac{3x-x}{2}]}{2\cos [\frac{3x+x}{2}]\cos [\frac{3x-x}{2}]}\\\\\Rightarrow \dfrac{2\cos 2x\sin x}{2\cos 2x\cos x}=\dfrac{\sin x}{\cos x}\\\\\Rightarrow \tan x[/tex]
Thus, all the identities are correct.
A. Not an identity
B. An identity
C. Not an identity
D. An identity
To check whether each expression is an identity, we need to verify if the equation holds true for all values of the variable x. If it is true for all values of x, then it is an identity. Let's check each option:
A. [tex]\((\sin x + \cos x)^2 = 1 + \sin 2x\)[/tex]
To check if this is an identity, let's expand the left-hand side (LHS):
[tex]\((\sin x + \cos x)^2 = \sin^2 x + 2\sin x \cos x + \cos^2 x\)[/tex]
Now, we can use the trigonometric identity [tex]\(\sin^2 x + \cos^2 x = 1\)[/tex] to simplify the LHS:
[tex]\(\sin^2 x + 2\sin x \cos x + \cos^2 x = 1 + 2\sin x \cos x\)[/tex]
The simplified LHS is not equal to the right-hand side (RHS) 1 + sin 2x since it is missing the sin 2x term. Therefore, option A is not an identity.
B. [tex]\(\sin 6x = 2 \sin 3x \cos 3x\)[/tex]
To check if this is an identity, we can use the double-angle identity for sine:[tex]\(\sin 2\theta = 2\sin \theta \cos \theta\)[/tex]
Let [tex]\(2\theta = 6x\)[/tex], which means [tex]\(\theta = 3x\):[/tex]
[tex]\(\sin 6x = 2 \sin 3x \cos 3x\)[/tex]
The equation holds true with the double-angle identity, so option B is an identity.
C. [tex]\(\frac{\sin 3x}{\sin x \cos x} = 4\cos x - \sec x\)[/tex]
To check if this is an identity, we can simplify the right-hand side (RHS) using trigonometric identities.
Recall that [tex]\(\sec x = \frac{1}{\cos x}\):[/tex]
[tex]\(4\cos x - \sec x = 4\cos x - \frac{1}{\cos x} = \frac{4\cos^2 x - 1}{\cos x}\)[/tex]
Now, using the double-angle identity for sine, [tex]\(\sin 2\theta = 2\sin \theta \cos \theta\),[/tex] let [tex]\(\theta = x\):[/tex]
[tex]\(\sin 2x = 2\sin x \cos x\)[/tex]
Multiply both sides by 2: [tex]\(2\sin x \cos x = \sin 2x\)[/tex]
Now, the left-hand side (LHS) becomes:
[tex]\(\frac{\sin 3x}{\sin x \cos x} = \frac{\sin 2x}{\sin x \cos x}\)[/tex]
Using the double-angle identity for sine again, let [tex]\(2\theta = 2x\):[/tex]
[tex]\(\frac{\sin 2x}{\sin x \cos x} = \frac{2\sin x \cos x}{\sin x \cos x} = 2\)[/tex]
So, the LHS is 2, which is not equal to the RHS [tex]\(\frac{4\cos^2 x - 1}{\cos x}\)[/tex]. Therefore, option C is not an identity.
D. [tex]\(\frac{\sin 3x - \sin x}{\cos 3x + \cos x} = \tan x\)[/tex]
To check if this is an identity, we can use the sum-to-product trigonometric identities:
[tex]\(\sin A - \sin B = 2\sin \frac{A-B}{2} \cos \frac{A+B}{2}\)\(\cos A + \cos B = 2\cos \frac{A+B}{2} \cos \frac{A-B}{2}\)[/tex]
Let A = 3x and B = x:
[tex]\(\sin 3x - \sin x = 2\sin x \cos 2x\)\(\cos 3x + \cos x = 2\cos 2x \cos x\)[/tex]
Now, we can rewrite the expression:
[tex]\(\frac{\sin 3x - \sin x}{\cos 3x + \cos x} = \frac{2\sin x \cos 2x}{2\cos 2x \cos x} = \frac{\sin x}{\cos x} = \tan x\)[/tex]
The equation holds true, so option D is an identity.
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Which ordered pair makes both inequalities true? y < 3x – 1 y > –x + 4 On a coordinate plane, 2 straight lines are shown. The first dashed line has a positive slope and goes through (0, negative 1) and (1, 2). Everything to the right of the line is shaded. The second solid line has a negative slope and goes through (0, 4) and (4, 0). Everything above the line is shaded.
Answer:
None of the options is true
Step-by-step explanation:
Given
[tex]y < 3x - 1[/tex]
[tex]y > -x + 4[/tex]
Required
Which makes the above inequality true
The missing options are:
[tex](4,0)\ (1,2)\ (0,4)\ (2,1)[/tex]
[tex](a)\ (x,y) = (4,0)[/tex]
Substitute values for x and y in the inequalities
[tex]y < 3x - 1[/tex]
[tex]0<3*4 - 1[/tex]
[tex]0<12 - 1[/tex]
[tex]0<11[/tex] ---- This is true
[tex]y > -x + 4[/tex]
[tex]0 > -4 + 4[/tex]
[tex]0 > 0[/tex] --- This is false
[tex](b)\ (x,y) = (1,2)[/tex]
Substitute values for x and y in the inequalities
[tex]y < 3x - 1[/tex]
[tex]2<3 * 1 - 1[/tex]
[tex]2<3 - 1[/tex]
[tex]2<2[/tex] --- This is false (no need to check the second inequality)
[tex](c)\ (x,y) = (0,4)[/tex]
Substitute values for x and y in the inequalities
[tex]y < 3x - 1[/tex]
[tex]4< 3*0-1[/tex]
[tex]4< 0-1[/tex]
[tex]4<-1[/tex] --- This is false (no need to check the second inequality)
[tex](d)\ (x,y) = (2,1)[/tex]
Substitute values for x and y in the inequalities
[tex]y < 3x - 1[/tex]
[tex]1<3*2-1[/tex]
[tex]1<6-1[/tex]
[tex]1<5[/tex] --- This is true
[tex]y > -x + 4[/tex]
[tex]1 > -2+4[/tex]
[tex]1 > 2[/tex] -- This is false
Hence, none of the options is true
Find the missing part.
Answer:
[tex]y=\frac{15\sqrt{3}}{4}[/tex]
Step-by-step explanation:
We are given that
[tex]\theta_1=60^{\circ}[/tex]
[tex]\theta_2=30^{\circ}[/tex]
We have to find the missing part.
[tex]\frac{x}{15}=cos\theta_1=cos60^{\circ}[/tex]
Using the formula
[tex]\frac{base}{hypotenuse}=cos\theta[/tex]
[tex]x=15cos60^{\circ}=\frac{15}{2}[/tex]
[tex]\frac{z}{15}=sin60^{\circ}[/tex]
Using the formula
[tex]\frac{Perpendicular\;arm}{hypotenuse}=sin\theta[/tex]
[tex]z=15\times \frac{\sqrt{3}}{2}=\frac{15\sqrt{3}}{2}[/tex]
Now,
[tex]\frac{a}{x}=cos60^{\circ}[/tex]
[tex]\frac{a}{\frac{15}{2}}=\frac{1}{2}[/tex]
[tex]a=\frac{1}{2}\times 15/2=\frac{15}{4}[/tex]
[tex]y=x sin60^{\circ}[/tex]
[tex]y=\frac{15}{2}\times \frac{\sqrt{3}}{2}[/tex]
[tex]y=\frac{15\sqrt{3}}{4}[/tex]
What is the simplest form of this expression?
Answer:
a is correct option......
for a project in her geometry class, amira uses a mirror on the ground to measure the height of her school’s football goalpost. she walks a distance of 14.45 meters from her school, then places a mirror on flat on the ground, marked with an x at the center. she then steps 3.65 meters to the other side of the mirror, until she can see the top of the goalpost clearly marked in the x. her partner measures the distance from her eyes to the ground to be 1.55 meters. how tall is the goalpost? round your answer to the nearest hundredth of a meter
Answer:
6.14 m
Step-by-step explanation:
If she moves 3.65 metres to the other side of the mirror. Her spouse calculates that there are 1.55 metres between her eyes and the earth. The height of the tail post is 6.14 m.
What is elevation?The distance up or down a specified point of comparison, most often a reference spherical geometry, a mathematical model of the Earth's sea level as an equipotential gravitational surface, determines a physical location's elevation.
Given that, after travelling 14.45 metres from her school, she lays a flat mirror on the ground in the centre, with an x drawn on it. When she can clearly see the top of the goalpost depicted in the x.
She moves 3.65 metres to the other side of the mirror. Her spouse calculates that there are 1.55 metres between her eyes and the earth.
Suppose the height of the tail post is x,
The geometric relation is,
1.55/3.65 = x/14.45
x=(14.45×1.55)/3.65
x=6.14 m
Thus, if she moves 3.65 metres to the other side of the mirror. Her spouse calculates that there are 1.55 metres between her eyes and the earth. The height of the tail post is 6.14 m.
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Make r the subject of the formula t = r/r - 3
Pls help asap
Answer:
statement not complete
The math club sold 15 novelty erasers and made a profit of
$7. After another week, the club had sold a total of 25
erasers and made a profit of $15. Which equation models
the total profit, y, based on the number of erasers sold, X?
A. y - 15 = 0.8(x - 7)
B. y - 15 = 1.25(x - 7)
C. y - 7 = 0.8(x - 15)
D. y - 7 = 1.25(x - 15)
Helppppp and explain pls and thankyouuu
Answer: B
Step-by-step explanation:
multiply all the the sales by 11% and you will get the answers in option b
ex: 1300*0.11=143
What is the answer to this question?
Answer:
yeah,I think it's 16 ...
Question 14
The coordinates of triangle ABC are A(2,3), B(2,-1), C(-1,-1). Describe the ordered pairs after the tranformation D3.
The ordered pairs of the transformation are A'(1,2), B'(1,-2), C'(-2,2) of the coordinates of the triangle ABC are A(2,3),B(2,-1),C(-1,-1).
What is meant by coordinates?
They are the points which together when jointed form a triangle.
How to do transformation of a triangle?
The transformation of triangle whose coordinates are as A(2,3), B(2,-1), C(-1,-1) is done as follows:
A'=(2-1,3-1)=(1,2)
B'=(2-1,-1-1)=(1,-2)
C'=(-1-1,-1-1)=(-2,-2)
Hence the ordered pairs are (1,2)(1,-2)(-2,-2).
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find the value of 5 + 8 / 4 * 3
Answer:
44
Step-by-step explanation:
5+8/4*3
5+24/4
20+24
44
Solve for x. Round to the nearest tenth of a degree, if necessary.
Answer:
x =48.6
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
sin theta = opp side / hypotenuse
sin x = 54 /72
Taking the inverse sin of each side
sin ^ -1( sin x) =sin ^-1 ( 54/72)
x = 48.59037789
To the nearest tenth
x =48.6
Answer:36.9
Step-by-step explanation:
please help -------------------- ASAPPP
Hello,
[tex]f^{-1}(f(58))=(f^{-1}*f)(58)=1(58)=58\\f(f(5)=f(9)=11\\[/tex]
The ages of Raju and Ravi arw the ratio of their ages will be 4:5 . Find their present ages.
Answer:
Step-by-step explanation:
The ages of Raju and Ravi are in the ratio 3:4 .Four years from now the ratio of their ages will be 4:5 . Find their present ages.
Ratio of ages at present = 3:4
Age of Raju = 3x
Age of Ravi = 4x
Age after four years:
Raju's age = 3x + 4
Ravi's age = 4x + 4
Ratio of ages after four year = 4 : 5
3x +4 : 4x + 4 = 4 : 5
(4x + 4)*4 = (3x + 4)*5
16x + 16 = 15x + 20
Subtract 16 from both sides
16x = 15x + 20 - 16
16x = 15x + 4
Subtract 15x from both sides
16x - 15x = 4
x = 4
Age of Raju = 3x = 3*4 = 12 years
Age of Ravi = 4x = 4*4 = 16 years
lidentify the domain of the function shown in the graph
O A 15257
O B. 19334
O C. 221
O D. All real numbers
Answer:
B.
Step-by-step explanation:
the visible line is the defined function.
this line goes from x=1 to x=4, and has the functional results from y=1 to y=7.
the domain is the valid interval of the input variable (typically x), while the range is the valid inescapable of the result variable (typically y).
so, B is the right answer.
How do angles inside a polygon affect the sides of the polygon?
Hello,
Let 's n the number of sides,
R the radius of the circonscrit circle,
c the side of the polygon (c like côté)
Angle in the center is 360/n and its half is 180/n
(c/2)/R=sin(180/n)
Inside angles are (180-360/n)/2 = 90-180/n (°)
Every floor of a 20 storey building is 5m in high. If a lift moves 2m every second, how long will it take to move from 3rd floor to 15th floor?
Answer:
30 seconds
Step-by-step explanation:
→ Work out how many floors it's going to travel
15 - 3 = 12 floors
→ Work out how many meters 12 floors is
12 × 5 = 60 meters
→ Work out how long that will take
60 ÷ 2 = 30 seconds
If / is a midsegment of /, find x.
A.
2
B.
3
C.
6
D.
9
Please select the best answer from the choices provided
A
B
C
D
Answer:
It is d
Step-by-step explanation:
Graph the function f(x)= -5(x+5)^2–4.
Plot the vertex. Then plot another point on the parabola.
Answer:
Vertex= (-5,-4)
Another point=(0, -129)
Step-by-step explanation:
The vertex is also the maximum, and the point is also the y-intercept.
A clothing store offers a free T- shirt when a customer spends $75 or more. Lyndon has already spent $36.95 which statement best represents all of the amounts he can spend to get a free T-shirt
A big box can hold 12 marbles and a small box can hold 5 marbles. There are a total of 99 marbles. How many big boxes are there?
Answer:
7 cajas grandes y 3 cajas pequeñas
Step-by-step explanatio:
factorise the following. x²-4
(x-2)(x+2) is factorize is given eq
Type the correct answer in the box. Solve the given equation by completing the square. x^2+ 8x = 38 Fill in the values of a, b, and c to complete the solutions
Answer:
A=2
B=8
C=-38
X=2.8/X=-6.8
Step-by-step explanation:
What is the rule for the following geometric sequence? 64,128,256,512...
a) a_(n) = 64(-2)^n-1
b) a_(n) = 64(2)^n-1
c) a_(n) = 64(1/2)^n-1
d) a_(n) = 64(-1/2)^n-1
Answer:
B
Step-by-step explanation:
The explicit rule for a geometric sequence is
[tex]a_{n}[/tex] = a₁ [tex](r)^{n-1}[/tex]
where a₁ is the first term and r the common ratio
Here a₁ = 64 and r = [tex]\frac{a_{2} }{a_{1} }[/tex] = [tex]\frac{128}{64}[/tex] = 2 , then
[tex]a_{n}[/tex] = 64 [tex](2)^{n-1}[/tex] → B
Answer:
b).
[tex]{ \tt{a _{n} = a( {r}^{n - 1} )}} \\ { \tt{a _{n} = 64( {2}^{n - 1}) }}[/tex]
PLEASE ASAP
c) Next, you will make a scatterplot. Name a point that will be on your scatterplot and describe what it represents.
d) Using the regression calculator in your tool bar, create a scatterplot using your data set from step 1. Insert a screenshot of your scatterplot, or recreate it below.
The data is in the pic below
If u want more points for the answer, pls answer the previous question (same one) in my profile worth 30 points)
THX
Answer:
C)Ok i pick the point (18,4)
this point represents that if this person studied from 18 hours they got a GPA of 4.0
D) the chart below is the scatter plot
Hope This Helps!!!
If you vertically compress the absolute value parent function, (x) = |X|, by a
factor of 4, what is the equation of the new function?
O A. g(x) = |4x|
O B. g(x) = 1/4 |x|
O C. g(x) = 4|x|
O D. g(x) = |x-4|
pls mark me as brainlist
thanks a lot
3. Sarah bought 3 pounds of apples for $6. How much did each pound of apples cost?
Answer:
A
Step-by-step explanation:
6/3 = 2
Answer:
$2 each
Step-by-step explanation:
3 pounds of apples for $6
$6÷3 lbs= $2 each pound
Which of the following is not a congruence theorem or postulate?
A.) AAS
B.) SSS
C.) AA
D.) SAS
Answer:
C.) AA
Step-by-step explanation:
AA is a similarity theorem
hope this helps stay safe :)
Answer:
The answer would be C.
Step-by-step explanation: Hope this helps :)
A researcher is curious about the average IQ of registered voters in the state of Florida. The entire group of registered voters in Florida is an example of a ______.
Answer:
Population
Step-by-step explanation:
A population can be defined as the total number of living organisms living together in a particular place and sharing certain characteristics in common.
A sample survey is a statistical method used for the collection of data from a target population in order to draw an inference and reach a logical conclusion.
In Statistics, sampling can be defined as a process used to collect or select data (objects, observations, or individuals) from a larger statistical population using specific procedures.
In this scenario, the entire group of registered voters in Florida is an example of a population.
