SOLUTION: What would the x-intercept for the equation y=x^3 -7/(x^2-4X-5)

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Question 962777: What would the x-intercept for the equation y=x^3 -7/(x^2-4X-5)
Answer by josgarithmetic(39627) About Me  (Show Source):
You can put this solution on YOUR website!
y=x%5E3+-7%2F%28x%5E2-4X-5%29

Let y=0.

0=x%5E3+-7%2F%28x%5E2-4X-5%29

x%5E3%28x%5E2-4X-5%29%2F%28x%5E2-4X-5%29-7%2F%28x%5E2-4X-5%29=0

Concentrate on the NUMERATOR being zero.

x%5E3%28x%5E2-4x-5%29-7=0

x%5E5-4x%5E4-5x%5E3-7=0

Use Rational Roots Theorem, or if necessary, graphing software to find roots.
Use of Google shows one real root at very very near to 5.002.