Question

y-6=√(2y-12)
y= ??

Answer 1

square both side
y2-12y+36 = 2y-12
y2-14y+48 =0
(y-6)(y-8)=0
y=6, y=8

Answer 2

y-6=√(2y-12)
(y-6)^2=(2y-12)
y^2-12y+36=2y-12
y^2-14y+48=0
y^2-6y-8y+48=0
(y-6)(y-8)=0
y=8 , y=8