If $3x + 2y = 18$ and $x = 2y - 2$, what is $x + y$?

Explanation

1. 01

   Substitute $x = 2y - 2$: $3(2y - 2) + 2y = 18$.

2. 02

   So $6y - 6 + 2y = 18$, giving $8y = 24$ and $y = 3$.

3. 03

   Then $x = 2(3) - 2 = 4$, and $x + y = 7$.