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Find the measure of the arc or central angle indicated. Assume that lines which appear to be diameters are actual diameters.

Find the measure of the arc or central angle indicated. Assume that lines which appear-example-1
User Dan Healy
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1 Answer

7 votes
7 votes

Answer: 238 degrees

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Step-by-step explanation:

Arc RTU is a semicircle of measure 180 degrees. This is because segment RU is a diameter of the circle.

Minor arcs RS, ST, and TU all combine to form arc RTU.

RS + ST + TU = RTU

x+70+52 = 180

x+122 = 180

x = 180-122

x = 58

Minor arc RS is 58 degrees in measure.

This means central angle RCS = 58 degrees, where C is the center of the circle.

Vertical angles are always congruent, which leads to central angle VCU being 58 degrees as well. This in turn leads to minor arc UV = 58.

In short, minor arc RS = minor arc UV = 58 degrees.

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So,

arc RTV = (arc RTU) + (minor arc UV)

arc RTV = (180) + (58)

arc RTV = 238 degrees

User Eugene Lopatkin
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