SOLUTION: 6x2-3x-45=0

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Question 71376: 6x2-3x-45=0
Answer by galactus(183) About Me  (Show Source):
You can put this solution on YOUR website!
Factor out a common factor...3
3%282x%5E2-x-15%29
Factor inside the parentheses. What two numbers when added equal -1 and when
multiplied equal -30. We must use -30 because of the leading coefficient 2. Because -15(2)=-30.
Those numbers are -6 and 5. (-6)(5)=-30, -6+5=-1
3%28%282x%5E2-6x%29%2B%285x-15%29%29
3%282x%28x-3%29%2B5%28x-3%29%29
3%28x-3%29%282x%2B5%29