Geometry

What does that mean?

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Three unit squares and two line segments connecting two pairs of vertices are shown. What is the area of triangle ABC?    

A is at (0,0), B is at (1,0), and C is at (1,1).   

Those three points make a right triangle.    

The base   is (0,0) to (1,0)  =  1 unit    

The height is (1,0) to (1,1)  =  1 unit    

The area of a triangle is (1/2) • base • height  =  (1/2) • 1 • 1  =  (1/2) unit²    

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