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How do you find the measure of angle b with only angle c and the outside of angle a

How do you find the measure of angle b with only angle c and the outside of angle-example-1

2 Answers

4 votes

Answer:

b = 36°

Explanation:

the exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.

117° is an exterior angle of the triangle , then

b + 81° = 117° ( subtract 81° from both sides )

b = 36°

User Eenoku
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12 votes

Explanation:

straight angle a + 117 = 180

a = 180 - 117

= 63

total angle in triangle = 180

63 + b + 81 = 180

b = 180 - 63 - 81

= 36

User Sharpper
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4.7k points