Question

question 10 of 10
in the diagram below, \\( \overline { a b } \\) is parallel to \\( \overline { c d } \\). what is the value
of \\( x \\)?

a. 80
b. 60
c. 100
d. 120

Explanation:

Step1: Use the property of adjacent angles

The adjacent angle of \(120^{\circ}\) is \(180 - 120=60^{\circ}\) (since the sum of adjacent angles on a straight line is \(180^{\circ}\)).

Step2: Use the property of parallel lines

Since \(\overline{AB}\parallel\overline{CD}\), the angle \(x\) and the angle calculated in step 1 are equal (alternate - interior angles are equal when two parallel lines are cut by a transversal). So \(x = 60\).

Answer:

B. 60