Question 92542
x^-2-9x^-1+18=0
It's a quadratic; the variable is x^-1.
Factor to get:
(x^-1-6)(x^-1-3) = 0
Since the product is zero one of the factors must be zero.
x^-1 = 6 or x^-1 = 3
Invert both sides to get:
x = 1/6 or x=1/3
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Cheers,
Stan H.