(3y-1)^2=(y-3)^2

问题描述:

(3y-1)^2=(y-3)^2

(3y-1)^2-(y-3)^2 =0
(3y-1+y-3)(3y-1-y-3)=0
(4y-4)(2y-4)=0
∴y1=1
y2=2

(3y-1)^2=(y-3)^2
9y^2 +1-6y=y^2+9-6y
8y^2=8
y^2=1
y为正负1

9Y^2 +1-6Y=Y^2 +9-6Y
8Y^2=8
Y^2=1
Y=正负1

9y^2+1-6y=y^2+9-6y
y^2=1
y=±1