Решите (3y+2)^2-9y=16

Question

Решите (3y+2)^2-9y=16

Answer 1

(3y +2)^2 -9y = 16
9y^2 +12y +4 -9y -16 = 0
9y^2 +3y -12 = 0 | /3
3y^2 +y -4 =0
D = 1 + 48 = 49

x = (-1 -7) / 6 = -8/6 = -4/3
x = (-1+7) / 6 = 6/6 = 1