WEBVTT
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If π₯ squared minus π equals π₯ plus five times π₯ minus five, what is the value of π?
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Hereβs what we know.
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We know that π₯ squared minus π is going to equal π₯ plus five times π₯ minus five.
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But to find out what the π value is, weβll need to multiply out π₯ plus five and π₯ minus five.
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Starting with our first term, weβll multiply π₯ times π₯ equals π₯ squared.
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π₯ times negative five equals negative five π₯.
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Five times π₯ equals five π₯.
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Five times negative five equals negative 25.
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We can bring down the first part of our problem: π₯ squared minus π.
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I wanna us to look closely at these two middle terms.
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They say negative five π₯ or minus five π₯ plus five π₯.
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What is five π₯ minus five π₯?
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Negative five π₯ plus five π₯ equals zero.
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Those two middle terms drop out.
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They cancel each other out.
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π₯ squared minus π equals π₯ squared plus zero minus 25.
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Or in completely simplified terms, π₯ squared minus π equals π₯ squared minus 25.
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So we know for sure our π value is 25.