Page 112 - Numeracy
P. 112
ANGLES & SHAPES
USING A PROTRACTOR
Look at your protractor, you will see that there are two sets of numbers.
One set goes from 0° to
180°. The other set
goes from 180° down to
0°. When we measure
an angle, we must
decide which is the
correct set of numbers to
use.
To the right are two angles.
You will see that the angles are at
different ends of the baseline.
When we place the protractor on the angle, we will use the set of numbers that
start at 0°.
Start at 0° not at 180° Start at 0° not at 180°
An angle of 80° An angle of 80°
Remember:
Angles are measured in degrees, e.g. 60°.
© SSER Ltd.
