# SAT Math: Using Common Denominators to Find an Equivalent Expression

Which of the following expressions is equivalent to ?

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00:19

it The expression could just flip flop our minds completely

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out of our skulls were not careful here So slow

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down few breasts and find our way through it So

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based on the answer choices it looks like this problem

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wants us to turn this mess into one nice fractional

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term Common denominators sound like a good starting point And

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if you look at the answer choices here their way

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starting with this mess right here and well then we're

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going to smoosh the whole thing together simplify the numerator

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and expand the denominator So that gets us quantity X

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plus seven plus quantity x plus five over quantity Exposed

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five times Explosive in all to the negative one And

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well funny thing we have What now Looks like two

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x plus twelve over X squared Plus twelve ax plus

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thirty five Power Interesting What do you think You get

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the negative one there That does not match It's wrong

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It's not a so what the power of negative one

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wants us to do remember is invert everything We invert

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the fraction so it's actually going to look like this

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X squared plus twelve expose thirty five over two X

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plus twelve which is B which is the right answer