In Fig. 8.127, AB||CD||EF and GH||KL. The measure of ∠HKL is
Given,
AB ‖ CD ‖ EF and GH ‖ KL
Produce HG to M and KL to N
∠MHD and ∠CHG = 60o (Vertically opposite angle)
Since,
MG ‖ NL and transversal cuts them
So,
∠MHD + ∠1 = 180o (Interior angles)
60o + ∠1 = 180o
∠1 = 120o
∠3 = ∠HKD = 25o (Alternate angles) (i)
∠1 = ∠MKL = 120o (Corresponding angles) (ii)
Now,
∠HKL = ∠3 + ∠MKL
= 25o + 120o
= 145o