Measuring Angles: Key Concepts and Techniques

What is the primary use of a protractor in geometry?

• To measure the size of an angle

• To draw perfect circles

• To calculate area of circles

• To measure the length of lines

Which direction should you move the protractor to measure an acute angle?

• Clockwise

• Perpendicular to the base

• Counterclockwise

• Does not matter

At what degree is the protractor aligned to measure an angle of 40 degrees?

• 100 degrees

• 80 degrees

• 40 degrees

• 0 degrees

What type of angle is measured if the protractor scale used is above 90 degrees?

• Acute

• Obtuse

• Straight

• Right

How do you find the measure of an unknown angle in a straight line setup?

• Add up known angles and subtract from 360

• Multiply known angles

• Add up known angles and subtract from 180

• None of the above

What are adjacent angles?

• Angles that sum up to 180 degrees

• Angles that sum up to 90 degrees

• Angles that share a common vertex and side but do not overlap

• Angles opposite to each other

What defines supplementary angles?

• Angles that are congruent

• Angles that are both acute

• Angles that add up to 180 degrees

• Angles that add up to 90 degrees

What is true about complementary angles?

• They add up to 90 degrees

• They add up to 180 degrees

• They are always obtuse

• They are always right angles

What does it mean for angles to be congruent?

• They are of the same measure

• They add up to 180 degrees

• They are adjacent to each other

• They are both right angles

How can you determine the measure of angle DEG using other angles?

• None of the above

• Add angles DEF and GEF

• Subtract angle GEF from DEF

• Multiply angles DEF and GEF