If You Divide 4 In. By 8 In. Rectangle From Corner To Corner, What New Shapes Do You Get?

You get two congruent right triangles when you divide a rectangle diagonally.

(This is one way to show that the area of each of those triangles is 1/2*base*height. Rectangle area = (4 in)(8 in) = 32 in². Triangle area = (1/2)(4 in)(8 in) = 16 in².)