SOLUTION: I have two questions. I am not sure if one goes here or not. I worked them but not sure if I did it right. Can someone please help? The diagonal of a square measures 4 inches. W

Algebra ->  Circles -> SOLUTION: I have two questions. I am not sure if one goes here or not. I worked them but not sure if I did it right. Can someone please help? The diagonal of a square measures 4 inches. W      Log On


   

Question 80411: I have two questions. I am not sure if one goes here or not. I worked them but not sure if I did it right. Can someone please help?
The diagonal of a square measures 4 inches. What is the length of the sides?
If the circumference of a circle is 5.68 X 109 feet, then what is its radius?
thanks so much!!
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Set up an equation for the diagonal, d , of the square
d+=+sqrt%282%29%2As where s is a side
4+=+sqrt%282%29%2As
solve for s
s+=+4+%2F+sqrt%282%29
multiply top and bottom by sqrt%282%29
s+=+2%2Asqrt%282%29 answer
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C+=+5.68%2A10%5E9
you know that
C+=+2%2Api%2Ar where r is the radius
2%2Api%2Ar+=+5.68%2A10%5E9
solve for r
r+=+5.68%2A10%5E9+%2F+%282%2Api%29
r+=+9.04000077%2A10%5E10 answer