Question

estimate the measure of this angle within 15°.

Explanation:

Step1: Recall angle - type knowledge

A right - angle is 90°. This angle is larger than a right - angle.

Step2: Estimate the angle

We know that a straight - angle is 180°. This angle looks like it is about two - thirds of 180°. $\frac{2}{3}\times180 = 120$. And it is within 15° of an accurate estimate for a visual estimation task.

Answer:

120