Respuesta :

cy - 7 = 5d + 3y...subtract 3y from both sides
cy - 3y - 7 = 5d....add 7 to both sides
cy - 3y = 5d + 7....factor out y on the left
y(c - 3) = 5d + 7...now divide both sides by (c - 3)
y = (5d + 7) / (c - 3) <===