Question

c. If the area of a circle is 121π square units, what is its diameter?

d. If the circumference of a circle is 20π units, what is its area?

Answer 1

c) A=pi r^2
it will give you r=11, right?
so, d=2r=22

Answer 2

area of a circle is defined as \[ \pi r^2 \] and the diameter as 2r. Plugin the value and you can solve problem c.

As for problem d, circumference is \[2 \pi r\], plugin the value and solve the equation.

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Answer 3

hi jasywasy4 i had posted u the formula earlier, refr to them and work out. :)

Answer 4

d) C=2pi r = 20pi
it will give you r=...
A=pi * r^2 =....
solve it

Answer 5

c.\[Pi r^2=121\Pi
hence r=11 hence d=22\]
d, 2 pi r=20 pi
r=10
hence area 100pi