Respuesta :

Since x = 3y + 15, plug that into the other equation.

5x + 2y = 7
5(3y + 15) + 2y = 7
15y + 75 + 2y = 7
17y = 7-75
17y = -68
y = -4

I hope this helps. (x = 3 and y = -4)