Question

what is the measure of angle 1 in the figure below? 80° 60° 40° 30°

Explanation:

Step1: Recall linear pair property

A linear pair of angles sums to \(180^\circ\). Let angle \(1\) be \(x\). So, \(x + 120^\circ=180^\circ\).

Step2: Solve for \(x\)

Subtract \(120^\circ\) from both sides: \(x = 180^\circ - 120^\circ\).
\(x = 60^\circ\).

Answer:

\(60^\circ\) (corresponding to the option with \(60^\circ\))