Answer:
Since the two base angles are congruent (same measure), they are each 70°. If we are given a base angle of say 45°, we know the base angles are congruent (same measure) and the interior angles of any triangle always add to 180°.
171-55=x
x= 116
to get the answer plug in the numbers and to check the answer reverse do the problem
97 is the answer to your question
