SOLUTION: If measures 135, what is the length of the radius of this circle? Round your answer to two decimal places.

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Question 273256: If measures 135, what is the length of the radius of this circle? Round your answer to two decimal places.

Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website!
if you are talking about the circumference of the circle, then the equation is:

c = 2*pi*r

When c = 135, this formula becomes:

135 = 2*pi*r

divide both sides of this equation by 2*pi to get:

r = 135/(2*pi) which makes r = 21.48591732

rounded to the nearest 2 decimal places, that becomes 21.49.

If you are talking about the area of the circle, then the equation for that is:

a = pi*r^2

When a = 135, this formula becomes:

135 = pi*r^2

divide both sides of this equation by pi to get:

42.97183463 = r^2

take square root of both sides of this equation to get:

r = sqrt(42.97183463) = 6.555290584

rounded to the nearest 2 decimal places, that becomes r = 6.56,