What is the result of subtracting the second equation from the first?
-2x+y = 0
-7x+3y = 2

Answer:

775

Step-by-step explanation:

We are given two equations in which we can perform systems of equations by putting these two equations on top of each other then solving for one variable:

x+y=15

x-y=25

Here, we can cancel out the y variable and get:

2x=40

x=20

Then we can put the x variable into any of the equations to solve for y (in this case I will use the equation x+y=15 so 20+y=15

y=-5

Now, we can solve by plugging both variables into 2x^2 - y^2 :

2(20)^2 - (-5)^2

800-25 = 775

I hope this helps!

Answer:

775

Step-by-step explanation:

Hi there!

We are given the following system of equations:

x+y=15

x-y=25

and we need to find the value of 2x²-y²

First, let's find the value of x and y

Let's add the 2 equations together to clear y and solve for x (y-y=0)

2x=40

divide both sides by 2

x=20

Now substitute 20 as x into either one of the equations to solve for y

To do x-y=25 for instance,

20-y=25

subtract 20 from both sides

-y=5

multiply both sides by -1

y=-5

Now we know that x=20 and y=-5

Substitute those values into the expression (remember: y² is equal to y×y, or (y)²)

2(20)²-(-5)²

Raise to the second power

2(400)-(25)

multiply and open parenthesis

800-25

subtract

775

Hope this helps!

Answer:

(D) 27 - C

Step-by-step explanation:

The "less than" means we are subtracting C from 27, so 27 - C.

Hope it helps (●'◡'●)

Answer:

2.4cm

Step-by-step explanation:

the area of a triangle is

baseline × height / 2

that means two lengths of the triangle have to be multiplied.

and to have 2 similar triangles means that all lengths inside one triangle are the corresponding lengths inside the other triangle multiplied by the scaling factor f.

multiplying 2 if these lengths with each other means also including the square of the scaling factor (multiplying with the scaling factor twice).

so, if the area of triangle 1 is

"baseline 1" × "height 1" / 2 = 45 cm²

then the area of triangle 2 is

"baseline 2" × "height 2" / 2 =

= "baseline 1"×f × "height 1"×f /2 =

= "baseline 1" × "height 1" × f² / 2 =

= ("baseline 1" × "height 1" / 2) × f² =

= 45 × f² = 20 cm²

f² = 20/45 = 4/9

f = 2/3

so, for a side of ABC being 3.6cm long, that means the corresponding side in DEF is

3.6 × f = 3.6 × 2/3 = 7.2/3 = 2.4cm

Answer:

the answer is D

Step-by-step explanation:

Answer:

just be smart

Step-by-step explanation: (2x)

Given:

The expression is:

[tex]b^2+20b[/tex]

To find:

The a monomial so that the trinomial may be represented by a square of a binomial.

Solution:

If an expression is [tex]x^2+bx[/tex], then be need to add square of half of coefficient of x, i.e., [tex]\left(\dfrac{b}{2}\right)^2[/tex] in the given expression to make in perfect square.

We have,

[tex]b^2+20b[/tex]

Here, coefficient of b is 20,so wee need to add square of half of coefficient of b, i.e., [tex]\left(\dfrac{20}{2}\right)^2[/tex].

[tex]\left(\dfrac{20}{2}\right)^2=10^2[/tex]

[tex]\left(\dfrac{20}{2}\right)^2=100[/tex]

Therefore, we need to add 100 to make [tex]b^2+20b[/tex] a perfect square binomial.

[tex]( - \frac{3}{4} )( \frac{7}{8} )[/tex]

[tex] = \frac{ - 3}{4} \times \frac{7}{8} [/tex]

[tex] = \frac{ - 21}{32} [/tex]

_______________________________________

[tex]( \frac{2}{3} )( - 4)(9)[/tex]

[tex] = \frac{2}{3} \times - 4 \times 9[/tex]

[tex] = \frac{ - 72}{3} [/tex]

[tex] = - 24[/tex]

_______________________________________

[tex]( \frac{5}{16} )( - 2)( - 4)( - \frac{4}{5} )[/tex]

[tex] = \frac{5}{16} \times - 2 \times - 4 \times \frac{ - 4}{5} [/tex]

[tex] = \frac{ - 160}{80} [/tex]

[tex] = \frac{ - 16}{8} [/tex]

[tex] = - 2[/tex]

_______________________________________

[tex](2 \frac{3}{5} )( \frac{7}{9} )[/tex]

[tex] = \frac{13}{5} \times \frac{7}{9} [/tex]

[tex] = \frac{91}{45} [/tex]

Answer:

5b: 3c = 25 : 16

Step-by-step explanation:

[tex] \frac{a}{b} = \frac{4}{5} \: and \: \frac{a}{c} = \frac{3}{4}[/tex]

dividing both to get a : c

[tex] \frac{a}{b} \times \frac{c}{a} = \frac{4}{5} \times \frac{4}{3} \\ \frac{c}{b} = \frac{16}{15} \\ [/tex]

inverting the fractions

[tex] \frac{b}{c} = \frac{15}{16} [/tex]

multiplying the numerator by 5 and denominator by 3

[tex] \frac{5b}{3c} = \frac{5 \times 15}{3 \times 16} \\ = \frac{75}{48} \\ = \frac{25}{16} [/tex]

therefore,

5b: 3c = 25 : 16

yes, it's a scaled version of a triangle with side lengths 3, 4 and 5.

by a factor of 20

a triangle with side lengths 3, 4 and 5 is a right triangle and it holds true for a²+b²=c², because 9+16=25

the 3,4,5-triangle is the simplest right triangle to calculate it's numbers seem somehow elegant.

the triangle in your problem is just a bigger version of it (wich means all angles stay the same).

My reasoning is lacking, but I'm sure

Answer:

[tex]( {4}^{3} \div {5}^{ - 2} {)}^{5} [/tex]

Step-by-step explanation:

[tex] {4}^{15} . {5}^{10} [/tex]

hope this will help you more

have a great day..

Step-by-step explanation:

[tex]( \frac{4 {}^{3} }{5 {}^{ - 2} } ) {}^{5 } \\ ( \frac{4 {}^{15} }{5 {}^{10} } ) \\ \frac{4 {}^{15} }{5 {}^{10} } [/tex]

Answer:

da

Step-by-step explanation:

Answer:

64->-?

Step-by-step explanation:

he spent 64 and now he has none so he spent all his money

Answer:

both lines have the same slope, hence they are parallel to each other

Step-by-step explanation:

The equation of a straight line is given by:

y = mx + b;

where y, x are variables, m is the slope of the line and b is the y intercept.

Two lines are said to be parallel to each other if they have the same slope, whereas two lines are perpendicular to each other if the product of their slopes is -1.

Given a line with an equation:

y = (2/3)x - 17

From the equation of the line with can see that the slope of the line is 2/3 and the y intercept is -17.

Also the other line has an equation of 4x - 6y = -6

6y = 4x + 6

y = (2/3)x + 1

Hence this line has a slope of 2/3 and a slope of 1.

Since both lines have the same slope, hence they are parallel to each other

Answer:

5/3*1/5= 1/3

Step-by-step explanation:

change the mixed fraction into improper fraction which is 1*3+2=5

then multiply

Answer:

4

Step-by-step explanation: This one is easy if you have 6 groups of ones then times it by 4 and you will get 24.

Answer:

N= 4

C=5

T=22

K=1

Step-by-step explanation:

Edge 2021

Answer:

Step-by-step explanation:

hope it helps

Answer:

parallel

Step-by-step explanation:

Let's rewrite each equation into the slope-intercept form so that we can easily identify the slope of each line.

slope-intercept form: y= mx +c, where m is the gradient and c is the y-intercept.

9x +3y= 12

3x +y= 4 (÷3 throughout)

y= -3x +4 -----(1)

24x +8y= 35

8y= -24x +35 (-24x on both sides)

[tex]y = - 3x+ 4 \frac{3}{8} [/tex] -----(2)

Thus, the slopes of the lines are both -3. Since both lines have the same gradient, they are parallel to each other.

Notes:

• parallel lines have the same gradient

• the product of the gradients of two perpendicular lines is -1

• gradient and slope has the same meaning and can thus be used interchangeably

Answer:

The probability that the average score of a group of n = 4 people is between 70 and 75=0.13591

Step-by-step explanation:

We are given that

[tex]\mu=65[/tex]

[tex]\sigma=10[/tex]

n=4

We have to find the probability that the average score of a group of n = 4 people is between 70 and 75.

[tex]P(70<\bar{x}<75)=P(\frac{70-65}{\frac{10}{\sqrt{4}}}<\frac{\bar{x}-\mu}{\frac{\sigma}{\sqrt{n}}}<\frac{75-65}{\frac{10}{\sqrt{4}}})[/tex]

[tex]=P(\frac{5}{5}<Z<\frac{10}{5})[/tex]

[tex]=P(1<Z<2)[/tex]

[tex]=P(Z<2)-P(Z<1)[/tex]

[tex]=0.97725-0.84134[/tex]

[tex]=0.13591[/tex]

Hence,  the probability that the average score of a group of n = 4 people is between 70 and 75=0.13591

[tex]\huge\boxed{\boxed{\underline{\textsf{\textbf{Answer}}}}}[/tex]

Given polynomial ⟹ 2x²+3y+5x²+2y

Terms are the values that come after each mathematical sign, like after ➺ +, -, ×, ÷

So,

Terms ⟹ 2x² , 3y , 5x² , 2y

No. of terms ⟹ 4 (option C)

Answer:

$49 hours

Step-by-step explanation:

12*40=$480

642-480= $162

$162/18= 9 hours more than 40

40+9=49 hours

Answer:

The answer is C

Step-by-step explanation:

Switch x and y

[tex]x = \frac{2y}{7} + 4[/tex]

Solve for y

[tex]y = \frac{7(x - 4)}{2} [/tex]

Answer:

C) or 1.25

Step-by-step explanation:

all you have to do is divide (thats how you undo multiplication)  150 and 120 (150/120) leading you to get 1.25.

HOPE THAT HELPED :D

Answer:

5.0956537e-46

Step-by-step explanation:

^ means root

* means multiply

f(x) = ab^x

f(-1.5)=26 = ab^-1.5

f(5.5)=7 = ab^5.5

f(5.5)/f(-1.5) = 26/7 = ab^5.5/ab^-1.5

3.714 = b^7

b = 3.714^-7

f(-1.5)=26 = ab^-1.5

26 = ab^-1.5

26 = a * 3.714^-7

a = 3.714^-7 / 26

a = 0.00000394578

f(10) = ab^10

f(10) = 0.00000394578 * (3.714^-7)^10

f(10) = 5.0956537e-46

Answer:

Step-by-step explanation:

If the table and ground are to be parallel then,

45° + x = 180° [Co-interior angles]

=> x = 180 - 45

=> x = 135° (Ans) (Option A)

[tex]\displaystyle\ \Large\boldsymbol p^q=16 \ \ then \\\\ 1) p=2 \ ; \ q=4 \Longrightarrow q^{pq}=4^{2\cdot 4}= 4^{8}=65536 \\\\\\2) p=4 \ ; \ q=2\Longrightarrow q^{pq}=2^{4\cdot2} =256[/tex]

Answer:

10 quarters and 12 dimes :)

Step-by-step explanation: