Question

In the adjoining figure, MN is parallel to PR, ∠LBN = 70° and AB = BC. Find the value of ∠ABC.

Answer 1

angle LBN=MBA=70

angle MBL=180-70=110

angle MBL=FAB=110

then BAC=ACB=70(isoceles triangle)

70+70+ABC=180

140+ABC=180

ABC=180-140

ABC=40