Question

Solve x2 + 12x = –20 by completing the square. Add to both sides of the equation. The value of in this equation is . Write the left side of the equation as a binomial squared. The left side of the equation becomes ()2. Use the square root property of equality. Isolate the variable: x =

Answer 1

x2+12x=-20 /-12x
x2=-20-12x /÷2 from the x2
x=-10-6x

Answer 2

x^2 +12x = -20
take the coefficient of X
divide it by 2
square that number
then add it to both sides of the equation.
12 / 2 = 6
6^2 = 36

x^2 +12x +36 = 16
(X+6) * (X+6) = 4*4
X+6 = 4 X= -2
X+6 = -4 X= -10