Question:
In the below fig, PQ ∥ AB and PR ∥ BC. If ∠QPR = 102°, determine ∠ABC Give reasons.
Solution:
AB is produce to meet PR at K
Since PQ ∥ AB
∠QPR = ∠BKR = 102° [corresponding angles]
Since PR ∥ BC
∠RKB + ∠CBK = 180° [Since Corresponding angles are supplementary]
∠CKB = 180 - 102 = 78
∴ ∠CKB = 78°