Question

can you explain how to decompose a rectangle into congruent triangles? how does the area of the decomposed pieces relate to the area of the rectangle?

Answer 1

You would divide the rectangle into half, to form two congruent triangles. When you multiply the area of 1 of the triangles, it gives you the area of both triangles, and so the area of the triangle as a whole.

Answer 2

Answer:

You would add a shape and find the whole area  of the two shapes together. Then you would subtract the area of the shape that you added to find the whole area of the rectangle.

Step-by-step explanation:

Hope this helps :)