Use the fact that any 4-sided figure has angles that add up to 360 degrees. Also use the fact that parallelograms cut by a transversal have alternate interior angles that are formed. If BD is the transversal cutting the parallelogram into 2 triangles, then 180-83-34 = 63. So angle A is 63. In a regular quadrilateral, the opposite angles are congruent. Therefore, angle C is also 63 (angle BCD). The alternate interior angle theorem helps us check ourselves for accuracy. 117+117+63+63 better equal 360. And it does!
