SOLUTION: Find the product of (3x-5)(2x^2+8x-7)

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Question 11655: Find the product of (3x-5)(2x^2+8x-7)
Answer by glabow(165) About Me  (Show Source):
You can put this solution on YOUR website!
First, think of the expression (2x^2+8x-7) as a number, a single number. Let's call it c. The first expression is (3x-5) which can be written (a+b).
What you have is (a+b)c. This, of course, is ac + bc.
Now put back what a, b, and c stand for.
You should get 3x%282x%5E2%2B8x-7%29+-+5%282x%5E2%2B8x-7%29
Can you do these two multiplications?
3x%282x%5E2%2B8x-7%29=6x%5E3%2B24x%5E2-21x
5%282x%5E2%2B8x-7%29=10x%5E2%2B40x-35
The whole thing looks like %286x%5E3%2B24x%5E2-21x%29-%2810x%5E2%2B40x-35%29
Which is 6x%5E3%2B24x%5E2-21x-10x%5E2-40x%2B35=6x%5E3%2B14x%5E2-61x%2B35