SOLUTION: find the circumference and area of a circle with diameter 6 inches, use 3.14 for pi

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Question 387456: find the circumference and area of a circle with diameter 6 inches, use 3.14 for pi
Answer by gwendolyn(128) About Me  (Show Source):
You can put this solution on YOUR website!
The equation for circumference is:
c=2%28pi%29r
The equation for area is:
a=%28pi%29r%5E2
First, we'll find the circumference.
The 'r' in the equation stands for radius. The radius of a circle is half of its diameter, so the circle's radius is half of 6--3 inches.
So, we can substitute 3 in for 'r' and 3.14 in for pi
c=2%28pi%29r
c=2%2A3.14%2A3
Then, we can simply multiply.
c=2%2A3.14%2A3
c=18.84
Therefore, the circumference of the circle is 18.84
Next, we'll find the circle's area.
Again, we can substitute 3 in for 'r' and 3.14 in for pi
a=%28pi%29r%5E2
a=3.14%2A3%5E2
The, we'll square three and multiply.
a=3.14%2A3%5E2
a=3.14%2A9
a=28.26
Therefore, the circumference is 18.84 and the area is 28.26.