Question

if 3x^2-2x+7=0, then (x-1/3)^2=?

Answer 1

3x^2-2x+7=0
x^2 - (2/3)x + (7/3) = 0
(x -1/3)^2 - 1/9 + 7/3 = 0
(x - 1/3)^2 = - 20/9

Answer 2

i see that you divided by 3 in the second equation but how did you derived at the third equation?

Answer 3

That is called "completing the square"

x^2 - (2/3)x
= (x -1/3)^2 - 1/9

Notice that when you expand (x -1/3)^2, you will get x^2 - (2/3)x + 1/9.

Is this help?