Calculator Soup
Calculator Soup: Rectangle Calculator
Use this calculator if you know 2 values for the rectangle, including 1 side length, along with area, perimeter, or diagonals and you can calculate the other 3 rectangle variables. A square calculator is a special case of the rectangle...
Calculator Soup
Calculator Soup: Parallelogram Calculator
Calculate certain variables of a parallelogram depending on the inputs provided. Calculations include side lengths, corner angles, diagonals, height, perimeter, and area of parallelograms.
Jim Loy
Jl's Math Page: The Golden Rectangle and the Golden Ratio
This is a personal site from Jim Loy that describes the golden rectangle and the golden ratio. Includes several diagrams and pictures as well as formulas. A good background in math is helpful.
Curated OER
Ic Teachers: Shapes Quadrilaterals
Are you looking for a very basic website that will explain the basic properties of a quadrilateral? Use this site to learn about the properties of a square, rhombus, rectangle, parallelogram, trapezoid, and kite. There are also some...
Curated OER
Rectangle
MathWorld provides the definition of a rectangle and the area formula of a rectangle.