I need help quick! (number 7, NOT 8!)

Use the linear combination method to solve this system of equations. What is the value of 3x+7y=3 X-7y=1

Allisa [31]

Answer:

look at the picture shown

4 0

3 years ago

the volume V of a gas at a constant temperature varies inversely with the pressure P. when the volume is 100 cubic inches the pr

fiasKO [112]

Answer:

The pressure is $20\ psi$

Step-by-step explanation:

we know that

A relationship between two variables, x, and y, represent an inverse variation if it can be expressed in the form $y*x=k$ or $y=k/x$

In this problem we have

$V*P=k$

where

V is the volume of a gas at a constant temperature

P is the pressure

we have

For $V=100\ in^{3}$ , $P=25\ psi$

step 1

Find the value of k

substitute the values of V and P

$100*25=k$

$k=2,500$

The equation is equal to $V*P=2,500$

step 2

Find the pressure when the volume is 125 cubic inches

For $V=125\ in^{3}$

substitute in the equation and solve for P

$125*P=2,500$

$P=2,500/125=20\ psi$

8 0

2 years ago

In XYZ, mX=90 and mY=30.In TUV,mU= 30 and mV=60. Which is true about the two triangles? XYZ=TUV, XYZ= VUT,No congruency statemen

Flauer [41]

Answer:

No congruency statement can be made because the side length are unknown.

Step-by-step explanation:

The sum of the measures of all interior angles in a triangle is always 180°.

In triangle XYZ,

$m\angle X=90^{\circ}\\ \\m\angle Y=30^{\circ},$

then

$m\angle X+m\angle Y+m\angle Z=180^{\circ}\Rightarrow m\angle Z=180^{\circ}-90^{\circ}-30^{\circ}=60^{\circ}$

In triangle TUV,

$m\angle U=30^{\circ}\\\\m\angle V=60^{\circ},$

then

$m\angle T+m\angle U+m\angle V=180^{\circ}\Rightarrow m\angle T=180^{\circ}-30^{\circ}-60^{\circ}=90^{\circ}$

We have two triangles with congruent angles but we have no information about side lengths. Therefore, can not be made because the side length are unknown. Correct option is last option.

6 0

3 years ago

Read 2 more answers

Brielle and Joshua are running a half marathon race, which is 13.1 miles long. It

Hitman42 [59]

Answer:Brielle will run the half marathon race faster.Brielle will take 1 hour 44 minutes and 48 seconds, Joshua will take 2 hours 37 minutes and 12 seconds

Step-by-step explanation:

10 / 1.25 = 8

8 minutes a mile

18 / 1.5 = 12

12 minutes a mile

Brielle will run the half marathon race faster.

8 x 13.1 =104.8

12 x 13.1=157.2

104.8 - 60=

44.8

60 seconds x .8= 48

Brielle will take 1 hour 44 minutes and 48 seconds

157.2 - 120 = 37.2

60 seconds x .2 = 12

Joshua will take 2 hours 37 minutes and 12 seconds

8 0

3 years ago

HELP A line passes through two points with coordinates (6,-8) and (-3,7).

FromTheMoon [43]

Answer:

Step-by-step explanation:

<u>Equation of the Line</u>

The equation of a line passing through points (x1,y1) and (x2,y2) can be found as follows:

$\displaystyle y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1)$

The line passes through the points (6,-8) and (-3,7), thus:

$\displaystyle y+8=\frac{7+8}{-3-6}(x-6)$

$\displaystyle y+8=\frac{15}{-9}(x-6)$

Simplifying:

$\displaystyle y+8=-\frac{5}{3}(x-6)$

Multiplying by 3:

$3(y+8)=-5(x-6)$

$3y+24=-5x+30$

Moving all the variables to the left side:

3y + 5x = 30 - 24

3y + 5x = 6

4 0

2 years ago