Measuring Angles with a Protractor

Mr. Ada teaches how to measure and estimate angles using a protractor. The lesson covers measuring acute and obtuse angles, including angles CBA, DAX, DEF, and JKL. Students learn to align the protractor correctly and count degree marks to determine angle measurements. Estimation techniques are also discussed, enhancing students' ability to approximate angle sizes accurately.

What tool is used to measure and draw angles?

• Ruler

• Set Square

• Compass

• Protractor

How do you align a protractor to measure angle CBA?

• Align the center with point B and the straight edge with ray BC

• Align the center with point C and the straight edge with ray BA

• Align the center with point B and the straight edge with ray BA

• Align the center with point A and the straight edge with ray AB

What is the measurement of angle CBA?

• 75°

• 70°

• 65°

• 60°

What is the first step in measuring angle DAX?

• Align the center of the protractor with vertex B

• Align the center of the protractor with vertex X

• Align the center of the protractor with vertex D

• Align the center of the protractor with vertex A

What is the estimated measurement of angle DEF?

• 40°

• 35°

• 34°

• 30°

How do you determine if angle JKL is obtuse?

• It is less than 90°

• It is more than 180°

• It is more than 90° but less than 180°

• It is exactly 90°

What is the actual measurement of angle JKL?

• 120°

• 122°

• 123°

• 130°