A parallelogram has both pairs of opposite sides parallel — and that one rule forces a lot: opposite sides equal, opposite angles equal, and the diagonals bisecting each other.
Drag the corners
parallelogram
area ≈ 109.4 sq units
Area
Height is the *perpendicular* distance between the two parallel sides — not the slanted side length.
Properties that come for free
- Opposite sides are equal and parallel.
- Opposite angles are equal; consecutive angles add to 180°.
- The diagonals bisect each other (they cross at their midpoints).
- Rectangles, rhombuses and squares are all special parallelograms — they just add right angles, equal sides, or both.
Watch out
Area is base × perpendicular height, not base × slanted side. Slide the top of the parallelogram above sideways: the side length changes, but if the height stays the same, so does the area.