Finding the Area of Triangles
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Objective
I can calculate the area of triangles using the formula A = 1/2 * b * h.
Part 1 of 4
Warm-up video
Math with Mr. J · 7:35Vetted channel
We don't generate video — this one is by Math with Mr. J on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
The area of a triangle can be found using the formula: Area = base × height ÷ 2.
- 2
When finding area, the units are always expressed as square units, such as square feet or square meters.
- 3
A triangle is exactly half of a rectangle or parallelogram, which is why we divide the base times height by two to find the area of a triangle.
Part 3 of 4
Practice
4 questions
What is the area of a triangle with a base of 10 cm and a height of 7 cm?
A triangle has an area of 20 square inches and a height of 5 inches. What is the length of the base?
Part 4 of 4
Exit ticket
Quick comprehension check
“A triangle has a base of 12 cm and a height of 7 cm. What is the area of the triangle? Show your work.”
Sample answer included in the free materials
Get the materials
Teacher guide, student handout, and slides — free, in Google Docs format
Teacher Guide
Complete lesson plan with answer keys and alternate activities
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