Question

-2x + 7y = 20
x + 7y = 32

Answer 1

(4,4)

Explanation:

1) Using substitution: move 7y to the other side by subtraction

x = 32 - 7y

2) substitute in for x in the first equation

-2(32 - 7y) + 7y = 20

3) distribute

-64 + 14y + 7y = 20

4) add like terms and solve for y

21y = 84

y = 4

5) plug in y value of for in one of the eqautions to get x value

-2x + 7(4) = 20

x = 4