Follow the process of completing the square to solve x2 - 10x + 8 = 0.

What is the value of the constant that will be isolated on the right side of the equation in step 3?

-32

-12

-8

Follow the process of completing the square to solve 2x2 + 8x - 12 = 0.

After adding B2 to both sides of the equation in step 4, what is the constant on the right side of the equation?

-32

112

160

Guest Jan 30, 2019

#1**+1 **

x^2 - 10x + 8 = 0 subtract 8 from both sides

x^2 - 10x = - 8 take 1/2 of 10 = 5....square it = 25 add to both sides

x^2 - 10x + 25 = - 8 + 25 factor the left and simplify

( x - 5)^2 = 17 take both roots

x - 5 = ±√17 add 5 to both sides

x = ±√(17) + 5

-8 was the isolated constant

2x^2 + 8x - 12 = 0 divide through by 2

x^2 + 4x - 6 = 0 add 6 to both sides

x^2 + 4x = 6 take 1/2 of 4 = 2.....square this = 4........add to both sides

x^2 + x + 4 = 6 + 4 factor the left and simplify

(x + 2)^2 = 10 take both roots

x + 2 = ±√10 subtract 2 from both sides

x = ±√(10) - 2

CPhill Jan 30, 2019