Question 145915
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(72)}}}
:
Factor inside the radical to reveal a perfect square
x - 8 = +/-{{{sqrt(36*2)}}}
:
Extract the square root of 36
x - 8 = +/-{{{6*sqrt(2)}}}
:
add 8 to both sides:
x = 8 + {{{6*sqrt(2)}}}
and
x = 8 - {{{6*sqrt(2)}}}