Q20 of 115 Page 8

In Fig 8.117, p is a transversal to lines m and n, ∠2 = 120° and ∠5 = 60°. Prove that m||n.

Given that,

∠2 = 120o


∠5 = 60o


To prove: ∠2 + ∠1 = 180o(Linear pair)


120o + ∠1 = 180o


∠1 = 180o – 120o


= 60o


Since,


∠1 = ∠5 = 60o


Therefore,


m ‖ n (As pair of corresponding angles are equal)


More from this chapter

All 115 →
18

The opposite sides of a quadrilateral are parallel. If one angle of the quadrilateral is 60° find the other angles.

 19

Two lines AB and CD intersect at O. If ∠AOC +∠COB+∠BOD = 270°, find the measures of ∠AOC, ∠COB, ∠BOD and ∠DOA.

 21

In Fig 8.118, transversal l intersects two lines m and n, ∠4= 110° and ∠7 = 65°. Is m||n?

 22

Which pair of lines in fig 8.119 are parallel? Given reasons