ShmoopTube

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And here's your shmoop du jour.

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Simplify the expression 5x2 + 6y2 - 4x2 + y2.

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And here are the potential answers...

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Before we spoil the ending, hit pause and try to solve it yourself.

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This question is testing whether we know how to add and subtract

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elements of an equation with exponents.

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This is what is usually referred to as "collecting like terms'...

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...meaning, the coefficients of terms with the same variable and exponent are added.

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The basic rule is that if they are of the same level of exponent --

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i.e. taken to the same power, then... yeah. We can.

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So in this equation we have 2 elements that are x squareds: 5x squared and negative 4x squared.

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Combine them and we just have... x squared.

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Same deal with y squared. We have 2 like elements:

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one is 6y squared and the other is just plain old y squared.

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These two add up to 7y squared.

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The whole equation now simplifies to x squared plus 7y squared.

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Answer: B. Finito.

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Next time we come over, we look forward to seeing your new "like term" collection...

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