Measuring, calculating and drawing angles... 0011 0010 1010 1101 0001 0100 1011 Our learning objectives today To use a protractor to: a) measure acute and.

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Transcript Measuring, calculating and drawing angles... 0011 0010 1010 1101 0001 0100 1011 Our learning objectives today To use a protractor to: a) measure acute and.

Measuring, calculating and
drawing angles...
0011 0010 1010 1101 0001 0100 1011
Our learning objectives today
To use a protractor to:
a) measure acute and obtuse angles to the nearest
degree.
b) draw acute and obtuse angles to the nearest
degree.
To calculate angles on a straight line.
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What do we use to help us?
0011 0010 1010 1101 0001 0100 1011
A protractor
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Here is a standard protractor like you
use in the classroom.
When we use a protractor, we
need to line it up correctly.
0011 0010 1010 1101 0001 0100 1011
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You need to make sure the protractor is lined up correctly.
Is this ready to measure the angle?
Were you right......................it wasn’t
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Look for the upside down ‘T’ in the middle of
the straight line on your protractor.
This needs to be exactly on the vertex of
your angle.
We need to remember.....
0011 0010 1010 1101 0001 0100 1011
It doesn’t
matter which
way round the
angle is, you
ALWAYS need
to line the upside
down ‘T’ to the vertex
of the angle.
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Now you are ready.
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Read from the 0°, and follow the inner set of
numbers.
Once you reach 30° you need to be
careful!!!
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You then need to look at the 1° markings on
the outer set of numbers.
What does it measure?
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This angle measures 35°.
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Measuring, calculating and
drawing angles...
Remember our learning objectives
today are
0011 0010 1010 1101 0001 0100 1011
To use a protractor to:
a) measure acute and obtuse angles to the nearest
degree.
b) draw acute and obtuse angles to the nearest
degree.
To calculate angles on a straight line.
1
2
4