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For you math wizards
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practice
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For you math wizards
On 04/15/2013 01:47 PM, Doug Miller wrote:
"Gramp's shop" wrote in news:384921f5-292d-40cc-9e3e-
:
I need to draw an arc for a piece of trim. The end points of the arc are 5 feet apart and the
depth of the arc at the center point is 2 inches. What is the radius of the circle?
224 inches
There ought to be an equation for this that would be far superior to trial and error, oui?
There is.
radius squared = (radius minus height) squared + (half the distance between endpoints)
squared
In this case:
r^2 = (r - 2)^2 + 30^2
r^2 = r^2 -4r +4 + 900
4r = 904
r = 226
Now we know how long a piece of string is!
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