Finding the Area of Composite Figures with Triangles | Math with Mr. J
From Math with Mr. J
6 min6thMath
Summary
How to find the area of triangles, parallelograms, and other polygons using their formulas. Mr. J shows where each formula comes from.
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Teaching resources
Discussion questions
Every area formula comes back to covering a shape with unit squares.
- How is the area of a triangle related to a rectangle?
- What is the formula for the area of a parallelogram?
- Why do you take half for a triangle?
Quick work-a-long
Words to know: area, base, height, triangle, parallelogram
- Find the area of a triangle with base 8 and height 5.
- Find the area of a parallelogram with base 6 and height 4.