What is the first correct step for solving the equation x^2 + x = 12?

Question

Is this it:  x^2 + x + 1/4 = 12 1/4   ?

Answer 1

Given: x²+x=12 ··· Eq.1  

First, subtract 12 from both sides to get the standard form of quadratic equation:

x²+x-12=0   Factor the left side of equation, getting

(x-3)(x+4)=0   Thus, we have either x-3=0 or x+4=0.   That is: x=3 or x=-4

CK: Plug x=3 or x=-4 into the left side of Eq.1:

3²+3=12 or (-4)²+(-4)=12   In either case LHS=RHS.   CKD.

The answer: x=3 or x=-4