Rectangles, Rhombi, and Squares

Geometry · Axiom Academy

LESSON Rectangles, Rhombi, and Squares Special parallelograms with unique properties 1. The Three Special Parallelograms Each shape below starts as an ordinary parallelogram, then adds one extra rule. That single rule cascades into a whole list of new properties — especially in how the diagonals behave. ✓︎ All parallelogram properties ✓︎ Diagonals are congruent (equal length) ✓︎ Diagonals bisect each other ✓︎ Diagonals are perpendicular ✓︎ Diagonals bisect the angles ✓︎ 4 equal sides AND 4 right angles ✓︎ Diagonals are congruent AND perpendicular Line the three shapes up side by side and the pattern becomes clear: the square's column is just the rectangle's and the rhombus's columns combined — wherever either earns a check, the square earns one too. You've seen how one extra rule turns a plain parallelogram into a rectangle, a rhombus, or — combining both — a square, the most special quadrilateral of all. Scroll up to revisit any step.

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