Page 41 - SPARK OF MATH book 6

(3-5) Measuring Angles.

Facts about angles:
• An angle is formed by two rays
from the same endpoint.

• The endpoint is called the vertex.
• We measure angles in units called

degrees. V

4 Types of Angles:
Obtuse Angle: an

Acute Angle: an angle angle which is between
which is less than 90°. 90° and 180°.

Right Angle: an angle Straight Angle: an angle
which is exactly 90°. which is exactly 180°.

To measure angles we need a tool called a ‘Protractor’

Step 1. Place the center point of the protractor on
the vertex of the angle.
A
Step 2. place 0 mark on one side of the angle.

Step 3. Read the measure of the angle where the
B
other side crosses the protractor.
C
The measure of the angle is 35°.

Use a protractor to find the measure of the given angles.

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