Page 18 - Key Stage 3 Geometry
P. 18
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clockwise the angles increase until you reach 180 on
the right-hand side. But you will notice there are two
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scales, from 0 on the right-hand side - working in an
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anticlockwise direction to 180 on the left-hand side.
An important point on the protractor is the cross-hairs
at the bottom centre. This is the point from where you
measure an angle or draw an angle.
Exercise 2-1
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Using your protractor, draw an angle of 50 .
Work through the following.
1. Using the ruler, draw a line of length 12 cm and
mark a dot in the middle of the line. Then place
your protractor on the line with the cross hairs
over the dot as shown below.
12
