The areas of a rectangle and a triangle

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Question from karen, a student:

how to calculate the shaded area of a triangle in a rectangle

Hi Karen,

Do you have a diagram like this?

triangle in rectangle

If so then join the peak of the triangle to the base by a line that is perpendicular to the base.

subdivided

The rectangle is then partitioned into 4 triangles that are congruent in pairs. How does the area of the triangle compare to the area of the rectangle?

Penny

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