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Look at the problem: (3x - 5)(x + 4)

Explain how to use the FOIL method to multiply the binomials.

User Diandrea
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1 Answer

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Answer: 3x^2 + 7x - 20

Explanation:

The foil method means:

First (multiply the first numbers in each binomial)

Outside (Multiply the first number in the first binomial and second number in the second binomial)

Inside (Multiply the second number in the first binomial with the first number in the second binomial)

Last (Multiply the second number in both binomials)


Therefore the equation can be simplified into: (3x * x) + (3x * 4) + (-5 * x) + (-5 * 4)


After simplifying further you get: 3x^2 + 12x - 5x - 20


You can now combine the 12x and -5x into 7x

User Pavium
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