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I need help
measure of each labeled angle

I need help measure of each labeled angle-example-1
User Chen Pang
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1 Answer

17 votes
17 votes

Answer:


\sf m\angle A = 3x - 20^o = \bf 100^o


\sf m\angle B = 2x = \bf 80^o


\sf m\angle C = 2x - 15^o = \bf 65^o

Explanation:

A figure is given to us , in which two lines are parallel to each other. There are two transversals to the || lines . We know that the measure of a straight line is 180° . Therefore ,


\sf\longrightarrow \angle A +\angle B = 180^o

Substitute the given values ,


\sf\longrightarrow 3x - 20^o + 2x = 180^o

Simplify the RHS by adding the variables ,


\sf\longrightarrow 5x - 20^o = 180^o

Add 20° to both sides ,


\sf\longrightarrow 5x = 180^o + 20^o

Add the numbers in RHS ,


\sf\longrightarrow 5x = 200^o

Divide both sides by 5 ,


\sf\longrightarrow \boxed{\blue{\sf x = 40^o}}

Therefore ,


  • \sf m\angle A = 3x - 20^o = \bf 100^o


  • \sf m\angle B = 2x = \bf 80^o


  • \sf m\angle C = 2x - 15^o = \bf 65^o

User Ian Cotterill
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