SOLUTION: I hope someone can help me with this: Solve by completing the square. Write the solutions in simplest radical form. The equation is x to the 2nd power - 16x = 8. Thanks for any hel

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: I hope someone can help me with this: Solve by completing the square. Write the solutions in simplest radical form. The equation is x to the 2nd power - 16x = 8. Thanks for any hel      Log On


   

Question 145915: I hope someone can help me with this: Solve by completing the square. Write the solutions in simplest radical form. The equation is x to the 2nd power - 16x = 8. Thanks for any help you can provide.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by completing the square. Write the solutions in simplest radical form. The equation is x to the 2nd power - 16x = 8.
;
:
x^2 - 16x + ____ = 8
:
Calculate the third term to complete the square,
Divide the coefficient of x by 2 and square the result: (16/2)^2 = 64
:
x^2 - 16x + 64 = 8 + 64; (add 64 to both side)
:
(x-8)^2 = 72
:
Find the square root of both sides:
x - 8 = +/-sqrt%2872%29
:
Factor inside the radical to reveal a perfect square
x - 8 = +/-sqrt%2836%2A2%29
:
Extract the square root of 36
x - 8 = +/-6%2Asqrt%282%29
:
add 8 to both sides:
x = 8 + 6%2Asqrt%282%29
and
x = 8 - 6%2Asqrt%282%29