WEBVTT
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Consider the expression four π₯ cubed π¦ squared minus five π₯ squared π¦ minus two π₯ cubed π¦ squared minus negative two π₯π¦ squared minus five π₯ squared π¦.
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Which of the following is equivalent to this expression? a) Two π₯ cubed π¦ squared minus two π₯π¦ squared. b) Two π₯ cubed π¦ squared minus 10π₯ squared π¦ plus two π₯π¦ squared. c) Two π₯ cubed π¦ squared minus 10π₯ squared π¦ minus two π₯π¦ squared.
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Or d) two π₯ cubed π¦ squared plus two π₯π¦ squared.
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To try and simplify this expression, we want to see if there are any like terms.
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Like terms have the same variable taken to the same power.
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We have four π₯ cubed π¦ squared.
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We also have two π₯ cubed π¦ squared.
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We combine these two like terms by combining their coefficients.
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We have four π₯ cubed π¦ squared and weβre subtracting two π₯ cubed π¦ squared.
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Four minus two is two.
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So combining these like terms will give us two π₯ cubed π¦ squared.
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From there, weβll just bring everything else down.
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Since weβre subtracting something inside the brackets, we need to distribute this subtraction.
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Weβre subtracting negative two π₯π¦ squared.
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We can rewrite that to say plus two π₯π¦ squared.
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Weβre also subtracting negative five π₯ squared π¦.
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And we can rewrite that as adding five π₯ squared π¦.
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We can bring down the rest of our equation, look again for any like terms.
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π₯ squared π¦ and π₯ squared π¦ are like terms.
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We combine these like terms by combining their coefficient.
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Negative five π₯ squared π¦ plus five π₯ squared π¦ will cancel out, leaving you with two π₯ cubed π¦ squared plus two π₯π¦ squared, option d.