If, l, m, n are three lines such that l||m and n l, prove that n m.

Given that,

l m and n perpendicular to m


Since, l m and n intersects them at G and H respectively


Therefore,


1 = 2 (Corresponding angles)


But, 1 = 90o as n is perpendicular to l


Therefore, 2 = 90o


Hence, n is perpendicular to m.


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