ShmoopTube

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And here's your shmoop du jour...

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If 3x squared - 6 = 18, what does x squared - 2 equal?

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And here are the possible answers...

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Ok, so the key to this problem is figuring out how 3x squared - 6 = 18 relates

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to x squared - 2.

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And no, he's not her second cousin.

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First, we see that both have an x squared in their equations...

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so let's try solving for that.

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Start with the first equation..

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Add 6 to both sides... so 3x squared = 24.

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Divide both sides by 3, and we have that x squared = 8.

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Now, we can plug x squared = 8 into the second equation:

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x squared - 2 = 8 - 2...which equals 6.

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The answer is A.

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