MATH
posted by Cindy .
Find the area of a circle with the given radius or diameter. Round your answer to the nearest tenth.
Diameter = 42.0 mm

A = pi * r^2
A = 3.14 * 21^2
A = 1,384.7 sq. mm 
radius = 42.0/2 = 21.0
A = pi r^2
= 3.14159 * 21 * 21
round answer to nearest tenth 
Never Mind!
Don't Answer this question! 
to square 21:
(20+1)(20+1) = 400 + 40 + 1 = 441 
Oh well :(

OK, Thanks!
Ms. Sue and Damon!
But I already got the answer!
It was 1,384.7 
You guys are very kind! :)

You are welcome :)
be sure you want mm^2, usually that would be converted to cm^2 or m^2
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