Two lines are respectively perpendicular to two parallel lines. Show that they are parallel to each other.
Given: Two lines m and n are parallel and another two lines p and q are respectively perpendicular to m and n, i.e., .
To prove
Proof:
Since m||n and p is perpendicular to m and n.
Similarly, q is perpendicular to m and n.
Now for lines p and q, m is the transversal
So we can see that all the conditions are fulfilled for the lines to be parallel, i.e., Corresponding angles are equal, sum of cointerior angles is 180o, alternate angles are equal.
Hence,
Hence proved