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And here's your shmoop du jour.

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Simplify the expression 2a to the fourth times 4a to the negative second.

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Here are the potential answers...

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

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Remember order of operations, or PEMDAS?

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Please excuse my dear aunt sally... or parentheses, exponents, multiplication/division, and addition/subtraction.

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PEMDAS tells us to work with the variables inside the parentheses first.

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2a and 4a can't get any simpler...

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...so we can move to the exponents.

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We have the quantity 2a to the 4th, which means that we take 2 to the 4th...

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...which is 16 times a to the 4th, so... 16a to the 4th.

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Next we have the quantity 4a to the negative second.

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Don't forget that little negative next to the 2 in the exponent.

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Remember that negative exponents basically just mean "1 over."

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We can move the 4a into the denominator and square it...which simplifies the fraction

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as 1 over 16 times a squared.

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When we multiply 16a to the 4th and one over 16 a-squared, we can cancel out the 16

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over 16 to 1 over 1... or 1.

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...and cancel the a to the 4th over a squared to a squared.

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This leaves us with a squared... or the answer... which also happens to be A.

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Now let's get out of here before Aunt Sally sets this whole place on fire.

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