The circumference of a circle is 20 pi. what is the radius of this circle?

Work Shown:

C = circumference = 20pi

d = diameter

C = pi*d

pi*d = 20pi

d = 20 after dividing both sides by pi

The radius is half the diameter, so r = d/2 = 20/2 = 10.

As an alternative, you can use the formula C = 2*pi*r

answer: 270

step-by-step explanation:

you have to times 200 by 1.35 to get your answer

center (1,3) with radius 6

step-by-step explanation:

we must complete the square to find the center and radius of the circle.

first make sure the x and y squared terms have 1 as their coefficients. we also make sure x and y terms together.

we now create space between the x and y terms with parenthesis.

we complete the square by taking the middle terms -2x and the -6y - divide each and square them.

we add the squares to both sides.

simplify.

and write the quadratics in factored form.

the center is (h,k) or (1,3). the radius is the square root of 36 which is 6.