Dimensions of a Rectangle Calculator
The Dimensions of a Rectangle Calculator finds the length and width of a rectangle from its area and perimeter by solving the resulting quadratic. Enter the area and perimeter.
Formula
Length + Width = P/2 and Length × Width = A; solve the quadratic
- Length and width are the roots of x² − (P/2)x + A = 0.
- A negative discriminant means no such rectangle exists.
Area 24, perimeter 20
Inputs
- Area: 24
- Perimeter: 20
l + w = 10 and l·w = 24 give length 6 and width 4.
Frequently asked questions
Can you find a rectangle from area and perimeter?
Yes, when a real solution exists. The sides are the roots of x² − (P/2)x + A = 0.