Question

A, B, C are three lines in the same plane. If line A is parallel to line B and line B is perpendicular to line C, then which of the following must be true for line C ?

• A. Line C is perpendicular to line A.
• B. Line C is paralle to line B.
• C. Line C is parallel to line A.
• D. None of the above

Answer 1

The correct option is A Line C is perpendicular to line A.

Given information can be represented as below;
Line A is parallel to line B and line B is perpendicular to line C i.e. angle formed between line B and line C is 90${}^{\circ }$.
Extend line C so that it intersects line A. Even here the angle formed is 90${}^{\circ }$.
$\therefore$ Line C is perpendicular to line A.