Question

The sum of interior angles of a pair of parallel lines,formed by a line that intersects the parallel lines is

• A. $0^{\circ }$
• B. ${90}^{\circ }$
• C. ${360}^{\circ }$
• D. ${180}^{\circ }$

Answer 1

The correct option is D ${180}^{\circ }$

When a third line intersects two lines and if the interior angles are less than ${180}^{\circ }$, they meet at a point if extended. But if the interior angles are exactly ${180}^{\circ }$ the figure obtained is a pair of parallel lines. Hence, the angle between two parallel lines are ${180}^{\circ }$.