Finding Perimeter when a Side Length is Missing (Composite Figures) | Math with Mr. J
From Math with Mr. J
5 min3rd4thMath
Summary
How to find the perimeter of a shape -- the distance all the way around -- by adding the side lengths. Mr. J keeps area and perimeter straight.
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Teaching resources
Discussion questions
Perimeter is the total distance around the outside of a shape.
- How is perimeter different from area?
- How do you find the perimeter of a rectangle quickly?
- What units is perimeter measured in?
Quick work-a-long
Words to know: perimeter, side length, distance around
- Find the perimeter of a 5-by-3 rectangle.
- Find the perimeter of a triangle with sides 4, 6, and 7.