X^2 - 8X - 18 = 0
X^2 - 8X = 18
take the coefficient of the X term,half it,square it and add it to both sides
X^2 - 8X + 16 = 18 + 16
X^2 - 8X + 16 = 34
factor the left side
(X - 4)^2 = 34
X - 4 = (+/-) sqrt(34)
X = (+/-) sqrt(34) + 4
This is the exact answer. For the HS answer..,
X = 9.8
X = - 1.8
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