y = 5x + 15

y = y

5 x + 15 = 10 x + 10

Divide both sides by 5

x + 3 = 2 x + 2

Subtract 2 to both sides

x + 1 = 2 x

Subtract x to both sides

1 = x

x = 1

y = 5 x + 15

y = 5 • 1 + 15 = 5 + 15 = 20

OR

y = 10 x + 10

y = 10 • 1 + 10 = 10 + 10

y = 20

The solution is:

x = 1 , y = 20

You can write solution as:

( 1 , 20 )