Question

an exterior angle of a triangle equals ______ minus the adjacent interior angle.
90
180
270
360

Explanation:

Step1: Recall linear pair property

An exterior angle and its adjacent interior angle form a linear pair, which means they are supplementary (their sum is \(180^\circ\)). So, if we let the exterior angle be \(E\) and the adjacent interior angle be \(I\), we have \(E + I=180^\circ\).

Step2: Solve for the exterior angle

Rearranging the equation \(E + I = 180^\circ\) to solve for \(E\), we get \(E=180^\circ - I\). This shows that an exterior angle of a triangle equals \(180^\circ\) minus the adjacent interior angle.

Answer:

180 (corresponding to the option "180")