Question 135843: Divide:
x2 – 9x + 20 ÷ x2 – 16
3x – 15 9x + 36
Answer by AlexxsDad(4)   (Show Source):
You can put this solution on YOUR website! I think you may have mis-typed the second problem. I don't see what's being divided. But I will help you with the first problem. Your problem is:
{x^2 - 9x + 20} / {x^2 - 16}
This is best solved by factoring both sides.
First the dividend (the left side): X^2 - 9x + 20 = {x-4}{x-5}
Then the divisor: {x^2 - 16} = {x+4}{x-4}
(this one is "difference of squares" factoring)
So once factored, your original problem is re-written as such:
{{x-4}{x-5}} / {{x+4}{x-4}}
Clearly, the {x-4} cancels on both sides, leaving the answer: {x-5} / {x+4}
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