Get Answers to all your Questions

header-bg qa

Two lines are respectively perpendicular to two parallel lines. Show that they are parallel to each other.

Answers (1)

Given: Two lines m and n are parallel and another two lines p and q are respectively perpendicular to m and n, i.e., p \perp m, p \perp n, q \perp m, q \perp n.
To prove
p \parallel q

Proof:

Since m||n and p is perpendicular to m and n.
\angle 5 = \angle 6 = \angle 7 = \angle 8 = \angle 11 = \angle 12 = 90^{\circ}
Similarly, q is perpendicular to m and n.
Ð\\angle 1 = \angle 2 = \angle 3 = \angle 4 = \angle 9 = \angle 10 = 90^{\circ}
Now for lines p and q, m is the transversal
\angle 1 = \angle 2 = \angle 3 = \angle 4 = \angle 5 = \angle 6 = \angle 7 = \angle 8 = 90^{\circ}
So we can see that all the conditions are fulfilled for the lines to be parallel, i.e., Corresponding angles are equal, the sum of interior angles is 180o, and alternate angles are equal.

Hence, p \parallel q

Hence proved

Posted by

infoexpert26

View full answer