SOLUTION: Rewrite the middle term as the sum of two terms and then factor completely 15X^2-21x+6 Thank you

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Question 90587: Rewrite the middle term as the sum of two terms and then factor completely
15X^2-21x+6
Thank you
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Rewrite the middle term as the sum of two terms and then factor completely
15X^2-21x+6
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Find two numbers whose product is 6*15=90
and whose sum is -21
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The numbers are -6 and -15
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Replace -21x by -6x-15x to get:
=15x^2-6x-15x+6
Factor the 1st two and the last two terms separately:
=3x(5x-2)-3(5x-2)
=(5x-2)(3x-3)
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Cheers,
Stan H.