# Rectangle Area Online Calculator (6 ways)

This online calculator will help you find the area of a rectangle. The solution can be found by six different methods.
Using this calculator, you can get a detailed step-by-step solution with an explanation and output of formulas. Thanks to this, you will be able to understand the algorithm for finding the area of a rectangle. You can also check the calculations that have already been performed.
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Rectangle area calculation method
Side a (or b): Radius R:

A rectangle is a geometric shape that has four right angles (90°) and opposite sides are equal and parallel.
Rectangle area formula or where R is the radius of the circumscribed circle, a or b - side.

Solution:
S =
4·R2-a2
=
99·4·762-992
=
99·23104-9801
=
99·13303
=
99·115.339
=
11418.561

a: The area of a rectangle with the radius of a circumscribed circle 76 and side 99 equal to 11418.561

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