What formulas are used?

With diagonals d₁, d₂: area = (d₁×d₂)/2, side = √((d₁/2)²+(d₂/2)²), perimeter = 4×side. With side and height: area = side×height.

Is a square a rhombus?

Yes. A square is a rhombus with all angles 90° and equal diagonals.

Calculate area and perimeter from diagonals, or from side and height. Area = (d₁×d₂)/2 or side×height.

Method

DiagonalsSide & height

Diagonal 1

Diagonal 2

What formulas are used?: With diagonals d₁, d₂: area = (d₁×d₂)/2, side = √((d₁/2)²+(d₂/2)²), perimeter = 4×side. With side and height: area = side×height.
Is a square a rhombus?: Yes. A square is a rhombus with all angles 90° and equal diagonals.

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