If you want to calculate the area of a rectangle, triangle, or circle in Excel, here is how you can do that. ... Now, the formula for the rectangle for C3 would become: =A3*B3.

The radius of the circle is 8 cm. Substitute 𝒓 = 8 into the formula for the area of the circle. Multiply π by the square of the radius. 3۰14 × 82 = 200۰96.