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Help! How do I factor this?

Help! How do I factor this?-example-1

2 Answers

2 votes
given <<5x^3-15x^2-140x>>
factor out everything in common
5x(x^2-3x-28)
factor polynomial within the parentheses
5x(x+4)(x-7)
User Kwelch
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7 votes
Given:
5x^3-15x^2-140x

Factor out a 5x:
5x(x^2-3x-28)

Find two numbers that multiply to -28 and add up to -3. In this case, -7 and 4:
5x(x-7)(x+4)
User Cristis
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8.4k points