Geometry

Question Analysis

This question involves measuring an angle using a protractor without a clear 0 - degree starting point. The main focus is on accurately reading the protractor's scale and calculating the angle's measurement.

 

Key Concept Explanation

A protractor has two scales (inner and outer). When both sides of the angle intersect the protractor away from 0°, we find the difference between the scale values on the same scale at the intersection points of the two sides with the protractor.

 

Step - by - Step Solution

1. Determine the scale:

Notice that the initial side of the angle is closer to the right - hand side  of the protractor, so we should use the inner - ring scale.

The inner - ring scale reading of the initial side is approximately .

The inner - ring scale reading of the terminal side is approximately .

 

2. Calculate the angle:

Subtract the initial side reading from the terminal side reading. So the measurement of the angle is

Click "Show Answer" to reveal the answer and analysis