Question

estimate the measure of this angle within 10°.

Explanation:

Step1: Recall right - angle property

A right - angle measures 90°.

Step2: Compare the given angle with right - angle

The given angle is less than a right - angle. By visual inspection, it seems to be around 45° (it is half of a right - angle approximately). Since we need an estimate within 10°, an estimate of 45° is reasonable.

Answer:

45°