In triangle ABD, you are given two angles, ABD and BDA. Their sum is 83° + 34° = 117°. Angle A (same as angle DAB) is, therefore, the supplementary angle to 117°, so the measure of the angle DAB is 180° - 117° = 63°. Angle BCD is the opposite angle in parallelogram ABCD to the angle DAB, so its measure is 63°. ANSWER