Question

Solve for x. Use the completing the square method. x² + 8x = 7

Answer 1

answer x=-4±√23

i took a test and got this right i hope this helps you  

Answer 2

Divide the coefficient by 2 then square the quotient.
Add the result to both sides of the equation.

$x^2 + 8x = 7$
$x^2 + 8x + (\frac{8}{2})^2 = 7 + (\frac{8}{2})^2$
$x^2 + 8x + 4^2 = 7 + 4^2$
$x^2 + 8x + 16 = 7 + 16$
$x^2 + 8x + 16 = 23$


Now, factor the left-hand side.

$x^2 + 8x + 16 = 23$
$(x + 4)^2 = 23$


Take the square root of both sides.

$(x + 4)^2 = 23$
$x + 4 = \sqrt{23}$
$x = -4$ ± $\sqrt{23}$