ShmoopTube

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Here’s your shmoop du jour, brought to you by 90 degrees

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Exactly 8 degrees less than these guys...

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Line j is parallel to line k, and line l bisects angle ABC.

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If y equals 117°, what is the measure of x?

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Sure is a lot of buzz around this new “Point B” place.

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Every line and angle seems to be hanging out there…

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…our guess is they’ve got some slammin’ fro yo.

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…we’ve got angle y and angle ABC, which are alternate interior angles.

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We know that because we’re told lines j and k are parallel.

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So those two HAVE to add up to 180, by definition. We don’t know the measure of angle x…

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…but we DO get the heads-up that line l bisects ABC… meaning that ABC equals 2x.

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So, really…we’re looking at the equation y plus 2x equals 180.

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We know y is 117 degrees… so

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117 plus 2x equals 180.

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Subtract 117 from both sides to get 2x = 63…

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…then divide both sides by 2, and x equals 31.5 degrees.

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Which is just a LITTLE warmer than the fro yo they’re serving at Point B.

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The flavor’s good, but it’s a little on the drippy side….

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