Respuesta :

emmagunther780
Answer:

17

Explanation:

(x + 8) + (8x + 1) = 90

Combine like terms to get:

9x + 9 = 90

Subtract 9 on both sides:

9x = 81

Divide by 9:

x = 9

Plug in 9 for x in
9 + 8 = ?

9 + 8 = 17