9514 1404 393
Answer:
- 54°
- both are 73°
- x = 12
Explanation:
Some useful relations are ...
A triangle inscribed in a semicircle is a right triangle.
Acute angles in a right triangle are complementary.
An inscribed angle is half the measure of the arc it intercepts.
The sum of arcs around a circle is 360°; 180° around a semicircle.
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1. Arc DF is twice the marked inscribed angle, so is 126°. Arc FE is supplementary to that, so is ...
arc FE = 180° -126°
arc FE = 54°
Alternate solution: arc FE is twice angle D, which is the complement of 63°.
2(90° -63°) = 2(27°) = 54° = arc FE
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2. Arc GJ = 360°-68° -31° -115° = 146°
angle GHJ = angle GIJ = 146°/2 = 73°
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3. arc UT = 2(90° -43°) = 94°
9x -14 = 94
9x = 108 . . . . . add 14
x = 12 . . . . . . . . divide by 9