Answer:
see explanation
Step-by-step explanation:
the figure is an isosceles trapezium
The legs are congruent , that is
BC = AD = 15 units
The upper base angles are congruent , so
∠ B = ∠ A = 145°
Any lower base angle is supplementary to any upper base angle, that is
∠ C + ∠ B = 180°
∠ C + 145° = 180° ( subtract 145° from both sides )
∠ C = 35°
The lower base angles are congruent , so
∠ D = ∠ C = 35°
