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Math Help: Area of squares, rectangles and triangles
Refresh your competency in the various areas of Mathematics.
This page from mathopenref.com explains how to find the area of a rectangle and then allows you to design rectangles and find their area. (NOTE: If the virtual manipulative does not work for you, try clicking the "full screen" button.)
This page from mathopenref.com shows you how to find the altitude (height) of a triangle and how to calculate the area. You can test knowledge by designing triangles and finding their area. (NOTE: If you have trouble with the manipulative, try clicking the "full screen" button.)