Question

Find the solution of 2x+2y=10 and x=5y+20

Answer 1

(15/2, -5/2)

Explanation:

1. Sub x=5y+20 into 2x+2y=10 and simplify as shown below.

2(5y+20)+2y=10

10y+40+2y=10

12y+40=10

12y=-30

y=-30/12

y=-5/2

2. Sub in y=-5/2 into 2x+2y=10 to find x and simplify as shown below.

2x+2(-5/2)=10

2x-5=10

2x=15

x=15/2