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How do you solve this

How do you solve this-example-1
User Robertp
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1 Answer

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Let
z^\circ be the measure of the unlabeled arc. Then


x^\circ+y^\circ+z^\circ=360^\circ

The arc with measure
y^\circ is subtended by a central angle of 180 degrees. We know this because the chord in the picture passes through the circle's center, so it must be the circle's diameter.

So we have


x^\circ+z^\circ=180^\circ

By the inscribed angle theorem, the inscribed angle of measure 36 degrees has half the measure of the central angle subtended by the same arc. This means
z^\circ=2\cdot36^\circ=72^\circ.

So


x^\circ=108^\circ

User Roberto Flores
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