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# How do you find the area of a circle when the radius is unknown?

Wiki User

2017-10-18 17:11:42

By using the other information supplied about the circle to calculate either its radius (from which its area can be calculated) or its area (if the circle is similar to another with a given area and some ratio between the two circle is given):

• If the diameter is given: radius = diameter ÷ 2
• If the circumference is given: radius = circumference ÷ 2π
• If the circle is similar to another circle which has a given area, and the length ratio is given; square the length ratio to get the area ratio and apply to the given area.

Wiki User

2017-10-18 17:11:42
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## A number a power of a variable or a product of the two is a monomial while a polynomial is the of monomials

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Wiki User

2017-10-17 22:38:05

The answer may depend on what other information you have about the circle.

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Q: How do you find the area of a circle when the radius is unknown?
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