Question 207700: factor trinomial with a-c method
3x^2+32x+45
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! factor trinomial with a-c method
3x^2+32x+45
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a time c = 3*45 = 135
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Think of two numbers whose product is 135 and whose sum is -32.
The numbers are 27 and 5
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Replace the 32y by 27y+5y
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3x^2+27x+5x+45
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Factor the 1st two and the last two terms separately:
3x(x+9) + 5(x+9)
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Factor again:
(x+9)(3x+5)
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Cheers,
Stan H.
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