ShmoopTube

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Here’s an unshmoopy question you’ll find on an exam somewhere in life.

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Which of the following should be the most appropriate first step in solving the

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equation 2x minus 17 over 9 equals 7?

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And here are the potential answers...

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OK, so this question is… kinda weird, really.

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There are lots of ways to approach it,

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so it’s tough to have a hard-wired MOST appropriate way to tackle.

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However, in this case, the BEST answer is probably getting rid of the fraction…

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…because they are just a pain to deal with, especially if we don’t have a laptop at our disposal.

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So intuitively multiplying both sides by 9

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would make sense as a first step and it’d simplify the world a whole lot.

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But let’s check out the other potential answers here.

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A – divide both sides by 2 – eih – that doesn’t really help us all that much.

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B – adding 17 to both sides really just confuses the issue – we can’t just add

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17 to the left side and make the negative 17 go away.

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That was kind of a curveball trick question. Thank you very much, test makers.

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And C – DIVIDING by 9 doesn’t help us at all – we’re then stuck with denominators

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of 81 on the left and a seven-ninths on the right. Blech. Ugly.

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So… ok, D it is.

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As in… “Denominators are pains in the butt.”

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