Explain how the formula for the area of a parallelogram is derived from that of a rectangle

Question

i Just need to know how is derived

Answer 1

parallelogram...draw vertikal line from rite end av base av parallelogram

This mark a triangel

muev that triangel tu left end & result=rektangel

Answer 2

I'm not really sure if this is right, but I think that the formula for finding the area of a parallelogram is derived form the formula for finding the area of a rectangle because while finding the are a parallelogram, you are basically finding the area of a rectangle and two congruent triangles. The L*W in the formula for finding the area of the parallelogram comes from the formula for finding the area of a rectangle (L*W). Since you still need to find the area of the two triangles, you take the /2 in the formula of a triangle ( (B*H)/2 ) and add it to the formula of the rectangle (L*W), resulting in (L*W)/2.

Again I'm not sure if this is correct as I am just a geometry student but I hope it helped in some way