This document provides a lesson on identifying, measuring, and calculating angles. It reviews that angles on a straight line add up to 180 degrees and uses this fact to have students calculate missing angles in several examples. These include angles of 86 degrees and 94 degrees, 37 degrees and 143 degrees, and others. The lesson objectives are to identify and measure acute and obtuse angles and use properties of angles on a straight line to find missing angles.

1. Angles
Lesson Objectives: -
•To be able to identify, estimate and measure
acute and obtuse angles.
•To be able to use information we know about
angles on a straight line to calculate the
missing angles.

2. Can you remember…..????
What do you know about angles on a
straight line?
How many degrees do they add up to?
Yes! You’ve got it………………...180°

3. Calculate the missing angle.
86°
94°

4. Calculate the missing angle.
37°
143°

5. Calculate the missing angle.
18°
162°

6. Calculate the missing angle.
37°
71°
72°

7. Calculate the missing angle.
21°
37°
63°
59°

8. Have we reached our objectives?
 To be able to identify, estimate and measure
acute and obtuse angles.
 To be able to use information we know about
angles on a straight line to calculate the
missing angles.