Mathematicians, it's a rainy day but Susanna Post, the 2021 Arkansas Teacher of the Year, is on the hunt. Can you help in her scavenger hunt to find examples of parallel and perpendicular lines? Rise ...

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 ...

The base and the perpendicular height are at right angles to each other. The measurements used must be in the same units. For example, to work in cm a 45 mm measurement would have to be converted to ...