Question

8. Given: AD perpendicullar DB, DB perpendicullar BC, AB = CD Prove: AB||DC​

Answer 1

Explanation:

Angle ADB = Angle CBD = 90° (given)

Side AB = Side DC (given)

Common side DB / BD

By HL congruence, triangles ABD and CDB are congruent.

Therefore Angle ABD = Angle CDB

=> Line AB is parallel to Line DC (Z angles)