Question

below are two parallel lines with a third line intersecting them. x = □

Explanation:

Step1: Identify angle - type relationship

The angle of 140° and the angle adjacent to \(x\) are corresponding angles. Since the two lines are parallel, corresponding angles are equal. So the angle adjacent to \(x\) is 140°.

Step2: Use linear - pair property

The angle adjacent to \(x\) and \(x\) form a linear - pair. The sum of angles in a linear - pair is 180°. Let the adjacent angle be \(a = 140^{\circ}\), then \(x+ a=180^{\circ}\), so \(x = 180 - 140\).

Answer:

40