How is the radius and area of a circle proportional

The factor '2 pi' is simply the constant of proportionality between C and R. So the area of a circle is proportional to R2 and pi is the constant of proportionality between the area and the radius of a circle.

The relationship between the area of a circle and the radius of the circle can be stated as follows: The area of a circle is proportional to the square of the radius.   Written in symbolic notation: A = R 2 RELATIONSHIP 5.1 Area = x (radius) squared OR A = R 2

Step-by-step explanation:

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step-by-step explanation:

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step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.