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

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