SOLUTION: Factoring Quadratic Expressions-- Directions; Factor each expression. Problem; 9x^2-36+27

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Question 565671: Factoring Quadratic Expressions--
Directions; Factor each expression.
Problem; 9x^2-36+27
Answer by Leaf W.(135) About Me  (Show Source):
You can put this solution on YOUR website!
1. Add like terms. 9x%5E2+-+36+%2B+27+=+9x%5E2+-+9
2. If possible, pull out a greatest common factor. Since both 9x%5E2 and -9 are divisible by 9, pull out that. 9x%5E2+-+9+=+9%28x%5E2+-+1%29
3. Factor x%5E2+-+1. Notice that x%5E2+-+1 is a difference of perfect squares. Any difference of perfect squares (a%5E2+-+b%5E2) can be factored as %28a+%2B+b%29%28a+-+b%29. 9%28x%5E2+-+1%29+=+9%28x+%2B+1%29%28x+-+1%29
4. Since 9(x + 1)(x - 1) cannot be factored any further, YOUR ANSWER IS 9(x + 1)(x - 1)
Hope I helped! =)