Question

Use substitution to solve the system.
x = 3y +7
3x + 4y = 8

Answer 1

x=4, y=-1

Explanation:

x=3y +7. equation 1

3x+4y=8. equation 2

substitute equation 1 into equation 2

3 (3y +7)+4y =8

9y+21+4y=8

13y+ 21=8

13y=8-21

y=-13/13

y=-1

substitute the value of y into equation 1

x=3(-1)+7

x=-3+7

x=4