Answers:
x = -3
base angle = 49 degrees
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Work Shown:
The missing angle is (2x+55) degrees since the base angles are congruent.
Add up the three angles and set the sum equal to 180. Solve for x.
(82)+(2x+55)+(2x+55) = 180
4x+192 = 180
4x = 180-192
4x = -12
x = -12/4
x = -3
Use this x value to find the base angle
B = base angle
B = 2x+55
B = 2*(-3)+55
B = -6+55
B = 49 degrees