Estimate Angles

In order to estimate a given angle, keep in mind a 90° angle (right angle).

A 90° angle looks like a corner of a rectangular piece of paper or a corner of a square.

Right angle

 

Let's look at an example.

Consider the angle given below.

 

3

 

Let's estimate the measure of this angle.

 

Observe that, the size of this angle is less than 90°.

 

3a

 

 

The size of this angle is
1 2
of the size of a right angle.

 

1
2
×  90°  =  45°

 

So, the estimate for the measure of the given angle is 45°.