Q4 of 23 Page 22

In figure 2.24, measures of some angles are shown. Using the measures find the measures of ∠ x and ∠ y hence show that line l ∥ line m.

Given: value of ∠ x and ∠ y


To find: line l ∥ line m


∠ y = 180-50 ° (linear pair angle) means that linear pair is a pair of adjacent, supplementary angle. Adjacent means next to each other, and supplementary means that measures of the two angles add up to equal 180 °.)


∠ y = 130 °


Transversal line making same angle to both line.


So, that line L ∥ line M.


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