Hi There!
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We Know:
1 angle is 100 degrees
The last 2 angles have the same measure.
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Find:
The measure of the last to angles.
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Solution:
A total triangle has to 180 degrees.
180 - 100 = 80
80 / 2 = 40
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Answer:
A and C both equal 40 degrees!
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Hope This Helps :)