Finding Measurement of Angles through Addition and Subtraction: 4th Grade Lesson
Solve addition and subtraction problems to find unknown angles. Scroll to the bottom of the article for the downloads.
Lesson Objective: The lesson is aligned to the Common Core State Standards for Mathematics – 4MD.7 Geometric Measurement – Recognize angle measure as additive.
Materials Required: Calculator
Identifying Measurement of an Angle using Addition and Subtraction
Use addition to find the angle measurement in degrees.
1. Find the measurement of angle a.
Students should be able to recognize when an angle is decomposed into non-overlapping parts, the angle measure of the whole is the sum of the angle measures of the parts. Students should be able to find the angle measure in degrees using addition or subtraction.