Learn how to calculate the areas of rectangle, triangle, and circle in Excel for a single cell or range of cells usin this formula.

Why is the area of a circle proportional to the square of its radius? And why is that ratio the same as the ratio of the circumference to the diameter?

Revise how to calculate the area of a triangle. Learn how to calculate the triangle's area by first finding the area of a rectangle in this BBC Bitesize maths guide.