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Course: Algebra basics > Unit 1
Lesson 9: Area of trianglesArea of triangles
Intuition for why the area of a triangle is one half of base times height.
Intuition for why the area of a triangle is
To see why the formula makes sense, drag the dot all the way to the right:
Whoa! You made a rectangle that's twice as big as the triangle! The area of the rectangle is square units, so the area of the triangle is square units.
Key intuition: A triangle is half as big as the rectangle that surrounds it, which is why the area of a triangle is one-half base times height.