WEBVTT
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Find the measure of angle ๐ถ.
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Hereโs angle ๐ถ.
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How should we find the measure of this angle?
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Well, fortunately for us, weโre given two different measures, measure of angle ๐ด and the measure of angle ๐ต that can help us.
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These two angles are vertical angles because theyโre opposite angles intersected by two lines.
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We know that vertical angles have the same angle measures.
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We can also find the measure of angle ๐ถ๐ต๐ด.
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Angle ๐ถ๐ต๐ด and angle ๐ด๐ต๐น are supplementary; they add up to one hundred and eighty degrees.
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They make a straight line, which means if we subtract one hundred and thirty four from one hundred and eighty, we can find the measure of angle ๐ถ๐ต๐ด.
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Angle ๐ถ๐ต๐ด is forty six degrees.
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We also know another key piece of information.
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The angles that make up a triangle always add up to one hundred and eighty degrees.
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We know two of the three angle measures of this triangle.
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Angle ๐ถ is that third measure.
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Fifty eight degrees plus forty six degrees plus the measure of angle ๐ถ equals one hundred and eighty degrees.
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We can add fifty eight plus forty six.
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Then we subtract one hundred and four degrees from both sides of our equation.
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One hundred and eighty degrees minus one hundred and four degrees equals seventy six degrees.
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The measure of angle ๐ถ equals seventy six degrees.