Will mark brainliest, help me answer this question!

135 degrees

Step-by-step explanation:

Angle CBD is the sum of angle ABC and angle ABD, so we find these firstAn Isosceles triangle has 2 equal sides and 2 equal anglesIsosceles triangle theorem tells us that the 2 equal angles are respectively opposite the equal sidesSince triangle ABC has sides AB=AC, then angle ACB = angle ABC So knowing that angles of triangle add up to 180, thenNow we do the next triangle to get ABDSince triangle ABD has sides AB=BD, then angle BDA = angle BAD So knowing that angles of triangle add up to 180, thenNow we said, angle CBD is the sum of angle ABC and angle ABD, so

This polygon has 4 sides
180(4-2) = 180(2) = 360 degree
80+90+2x + 3x = 360
170+5x = 360
5x = 190
x= 38
measure of angle t is 2(38)= 76
the answer is c. trust me
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