Guided Practice
Learn
In this guided practice lesson, you will apply what you've learned about measuring angles and identifying angle types. Work through each problem step by step, using your protractor skills and angle classification knowledge.
Key Skills to Practice:
- Using a protractor to measure angles accurately
- Classifying angles as acute, right, obtuse, or straight
- Estimating angle measures before measuring
- Drawing angles of specific measures
Examples
Work through these guided examples to reinforce your understanding.
Example 1: Measuring and Classifying
Given an angle, first estimate whether it is acute, right, or obtuse. Then measure it with a protractor to verify.
Example 2: Finding Missing Angles
Two angles on a straight line must add up to 180 degrees. If one angle is 65 degrees, the other is 180 - 65 = 115 degrees.
Practice Quiz
Test your understanding with these 10 practice questions. Click on each question to reveal the answer.
Question 1: An angle measures 45 degrees. What type of angle is it?
Answer: Acute angle. Any angle less than 90 degrees is acute.
Question 2: What is the measure of a right angle?
Answer: 90 degrees. A right angle forms a perfect square corner.
Question 3: An angle measures 120 degrees. Is it acute, right, or obtuse?
Answer: Obtuse. Any angle greater than 90 degrees but less than 180 degrees is obtuse.
Question 4: Two angles on a straight line add up to how many degrees?
Answer: 180 degrees. A straight line forms a straight angle of 180 degrees.
Question 5: If one angle on a straight line measures 70 degrees, what does the other angle measure?
Answer: 110 degrees. Since 70 + 110 = 180 degrees.
Question 6: Which is larger: an acute angle or an obtuse angle?
Answer: An obtuse angle is larger. Obtuse angles are greater than 90 degrees, while acute angles are less than 90 degrees.
Question 7: What tool do we use to measure angles?
Answer: A protractor. Place the center point on the vertex and align one ray with the baseline.
Question 8: An angle measures exactly 90 degrees. What special name does this angle have?
Answer: A right angle. Right angles are often marked with a small square symbol.
Question 9: If you turn one-quarter of the way around a circle, how many degrees have you turned?
Answer: 90 degrees. A full circle is 360 degrees, so one-quarter is 360 / 4 = 90 degrees.
Question 10: An angle measures 180 degrees. What type of angle is this?
Answer: A straight angle. It forms a straight line.
Check Your Understanding
Review your answers above. If you got 8 or more correct, you're ready to move on. If you scored below 8, review Lessons 1 and 2 before continuing.
Next Steps
- Review any concepts that felt challenging
- Practice drawing angles with a protractor
- Move on to Word Problems to apply these skills in real-world contexts