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➷ Isosceles base angles are equal
Therefore, the other base angle would also be 54 degrees
Angles in a triangle total to 180 degrees
Now you can calculate:
180 - (54 + 54) = 72
The vertex angle is 72 degrees.
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➶ Hope This Helps You!
➶ Good Luck (:
➶ Have A Great Day ^-^
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