BBC1 年
How to show the area of a parallelogram is base × height
Image caption, STEP 1: Use the ruler and pencil to draw a diagonal line from the bottom ... You’ve proven that the area of a parallelogram is the same as a rectangle with the same base and ...
BBC11 个月
Interior and exterior angles
The opposite sides are parallel. The diagonals bisect each other. The exterior angles of a rectangle are each 90°. A parallelogram has two pairs of equal sides. It has two pairs of equal angles.