Question

Find the value of A A. 450 B. 550 C. 400 D. 500

Answer 1

Answer:

40°

Step-by-step explanation:

For convenience I've marked the diagram with point being named.

Now, ∠YTP = 180° - 110° = 70°

∴ ∠QPT = 70° + 40° = 110° [∵ exterior angle = sum of other two angles]

Now, ∠UPQ = ∠UQP = 180° - 110° = 70°

Now, ∠A = 180° - (70° + 70°) = 40°        [angle sum theorem]