ShmoopTube

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Here's your shmoop de jour

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Solve for a using substitution: 4a = b - 8

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a + b = 18

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And here are the potential answers...

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OK fun problem.

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It's another one of those problems that wants us to put our super-duper substitution skills

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to work.

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We want to get either a or b alone. Like what is a simply or what is b simply

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In the first equation, b's already by itself...

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...so we can just add 8 to both sides to get b = 4a + 8.

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Plugging that into the other equation in place of b, we get a + 4a + 8 = 18...

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...and when we slap our a terms together and subtract 8 from each side...

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...we're left with 5a = 10. Divide both sides by 5, and a = 2.

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Our answer is B.

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As in, "Binomial Man."

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