Question

A family has two cars. The first car has a fuel efficiency of
25

miles per gallon of gas and the second has a fuel efficiency of
15

miles per gallon of gas. During one particular week, the two cars went a combined total of
1025

miles, for a total gas consumption of
55

gallons. How many gallons were consumed by each of the two cars that week?

Answer 1

Answer:

15x+25y=975

x+y=55

Rearrange equation two so x is by itself.

x=-y+55

Plug the rearranged equation two into equation one.

15(-y+55)+25y=975

Evaluate the 'new' equation 1.

-15y+825+25y=975

10y+825=975

10y=150

y=15

Choose an equation to evaluate with y to get x. (i chose equation 2 because it was easier)

x+15=55

Evaluate the equation

x=55-15

x=40

So now we have x=40 and y=15

Evaluate those two terms with both equations to check the correctness.

15(40)+25(15)=975

600+375=975

975=975 (correct)

40+15=55

55=55 (correct)

Both equations are correct so the values of x and y are true.

Please mark as brainliest. :)