SOLUTION: Completing the square. Please walk me through each step. the text says the answers are x=10, x=-2 x^2 - 8x - 20 = 0 thank you

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Completing the square. Please walk me through each step. the text says the answers are x=10, x=-2 x^2 - 8x - 20 = 0 thank you      Log On


   

Question 396264: Completing the square.
Please walk me through each step. the text says the answers are x=10, x=-2
x^2 - 8x - 20 = 0
thank you
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

x^2 - 8x - 20 = 0   |Completing the square

(x-4)^2 -16 - 20 = 0  |Note:(x-4)^2 -16 = (x^2-8x+16) -16 = x^2-8x

  (x-4)^2 = 36

  (x-4) = ± 6

   x-4 = 6

     x = 10

   x-4 = -6

     x = -2