Question

Which of the following is the result of completing the square for x2 + 8x - 6 ?

Answer 1

x^2+8x-6=0
(x+8/2)^2-(8/2)^2-6=0
(x+4)^2-16-6=0
(x+4)^2-22=0

x+4= ± square root 22

x=-4 + square root 22 or x=-4 - square root 22
=0.6904 =-8.6904

Answer 2

STEP 1- since 6 doesn't contain the variable to solve for move it to the right side of the equation by subtracting 6 from both sides
X^2-8X=-6
STEP 2- create a trinomial square on the left side of the equation find the value that is equal to the square of half of b the coefficient of x
(b/2)^2 =(-4)^2
STEP 3- add the term to each side of the equation
x^2-8x+(-4)^2=-6=(-4)
STEP 4- simplify the equation
x^2-8x+16=10
STEP 5- factor the perfect trinomial square into (x-4)^2
(x-4)^2=10
STEP 6-solve the equation for x
x=4= square root of 10