● Interactive · IH01 explorable

Area = w × h

Don't take the formula on faith — drag the sliders and watch the rectangle and its area move together. The rule is something you derive, not memorize.

6 × 4 = 24

area scales with both sides — double one, double the area

Width (w) 6

Height (h) 4

Try setting w = 12, h = 1 vs w = 4, h = 3 — same area, very different shape.