Measuring with Protractor

Using a Protractor

​Essential question

​

How can we use a protractor to measure angles?

Some text here about the topic of discussion

Protractor WARNING!

Protractors have two sets of numbers going in opposite directions. One is closer to the inside and the other is towards the outside.

Be careful which you use!

Which numbers (inside or outside) should we be using to determine the angle?

The angle is ACUTE so we know it is less than 90º so we use the inside numbers highlighted yellow.

Which numbers (inside or outside) should we be using to determine the angle?

The angle is OBTUSE so we know it is greater than 90º so we use the inside numbers highlighted yellow.

Take a good look at this angle. Figure out the measurement.

Multiple Choice

A right angle is at what degree

• 180

• 20

• 90

• 80

Multiple Choice

Another name for a right angle is ___________.

• square angle
• correct angle
• 90 degree angle
• none of the above

Multiple Choice

What tool do we use to measure angles?

• Protractor

• Ruler

Multiple Choice

• 120 degrees

• 80 degrees

• 100 degrees

• 0 degrees

Multiple Choice

• 145 degrees

• 155 degrees

• 35 degrees

• 0 degrees

Multiple Choice

• 20 degrees

• 160 degrees

• 180 degrees

• 0 degrees

Multiple Choice

• 180 degrees

• 125 degrees

• 55 degrees

• 65 degrees

Multiple Choice

• acute

• right

• obtuse

Multiple Choice

• acute

• right

• obtuse

• none of the above

Multiple Choice

• acute

• right

• obtuse

• none of the above

Multiple Choice

• acute

• right

• obtuse

• none of the above