The base and perpendicular height are at right angles. Showing that a parallelogram has the same area as a rectangle: Split the parallelogram into a right-angled triangle and a trapezium. Move the ...

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. What is a quadrilateral? A quadrilateral is a four-sided shape where each of the sides are straight and ...

Quite so. The problem with parallelograms is that they’re a con. They tell you that finding the area is simple: it’s base · height. Easy peasy! But what’s the height? Crap. The length of the sides isn ...

Proving that two polygons have the same area can be as easy as cutting them up and rearranging the pieces. Gina the geometry student stayed up too late last night doing her homework while watching The ...

A new survey of the dimensions and orientation of ancient Egypt’s Great Pyramid of Giza has found that its builders attained a remarkable degree of accuracy despite limited technology. The ...