Question

estimate the measure of this angle within 10°.

Explanation:

Step1: Recall angle - type knowledge

An acute angle is less than 90°. A right - angle is 90°. An obtuse angle is greater than 90° but less than 180°. This angle is clearly acute.

Step2: Make an estimate

We know that a 45° angle would have the two rays symmetrically placed with respect to the perpendicular and horizontal directions. This angle is a bit more open than 30° and less open than 60°. A reasonable estimate is 60°.

Answer:

60