SOLUTION: x^2-1=8x Enter the exact answers in increasing order. (formula)

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Question 1014683: x^2-1=8x
Enter the exact answers in increasing order. (formula)
Answer by skippo(9) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-1=8x
using method of completing the square
x%5E2-8x=+1
add 16 to both sides
x%5E2-8x%2B16 = 1+%2B16
x%5E2-8x%2B16 = 17
%28x-4%29%5E2 = 17
x-4 = +-+sqrt%2817%29
x = -+sqrt%2817%29%2B4 or %2B+sqrt%2817%29%2B4
x = -4.123%2B4 or 4.123%2B4
x = -0.123 or 8.123