Question

X^2 - 6 = -2x
Find the solution by completing the square

Answer 1

x = -1±sqrt( 7)

Explanation:

x^2 - 6 = -2x

Add 2x to each side

x^2 +2x- 6 = -2x+2x

x^2 +2x -6 = 0

Add 6 to each side

x^2 +2x- 6+6 = 6

x^2 +2x = 6

Take the coefficient of x

2

Divide by 2

2/2 =1

Square it

1^2 =1

Add this to each side

x^2+2x+1 = 6+1

(x+1)^2 = 7

Take the square root of each side

sqrt((x+1)^2) =±sqrt( 7)

x+1 = ±sqrt( 7)

Subtract 1 from each side

x+1-1 = -1 ±sqrt( 7)

x = -1±sqrt( 7)