Question

Solve x2 + 12x + 6 = 0 using the completing-the-square method.

Answer 1

X^2+12x+6=0  subtract 6 from both sides...

x^2+12x=-6  halve linear coefficient, square it, and add it to both sides...

x^2+12x+36=30  now the left side is a perfect square...

(x+6)^2=30  take square root of both sides...

x+6=30^(1/2)  subtract 6 from both sides...

x=-6-30^(1/2) and -6+30^(1/2)