A parallelogram has an area of 54 square centimetres and a base of 9 centimetres. What is its perpendicular height?

Erklärung

No half appears in the parallelogram rule, so the height is 54 divided by 9 and nothing more. Doubling the area first returns 12 and imports a step that belongs to triangles, which would make this shape twice as tall as it really stands.