Question 177639: Factor completely. 20x^2 – 3x – 9
Answer by MathTherapy(10552) (Show Source):
You can put this solution on YOUR website! We 1st need to multiply “c” by “a,” which gives us – 9 x 20 = - 180
Now, we need to find 2 factors that when multiplied, they give us – 180, and when added, they give us – 3 (“b”). These 2 factors are: - 15 and 12
We then use the GCF of each binomial to factor each one, starting with the 1st
5x(4x - 3) + 3(4x - 3). Make sure that the two binomials, in parentheses (4x – 3), are equal.
Therefore, the factors are: (5x + 3)(4x - 3)
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