# Error "unable to solve" using NSolve on circle-equation

Posted 3 months ago
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 HalloI would like to solve a circle equation. I use Mathematica with Raspberry.1.) I defined variables c=-90, d=27, r=10 , x=33,6777 2.) I wrote: NSolve[(x - c) ² + (y - d)² == r² , {y}, Reals] 3.) I'm interested in y4.) as a result I receivedNSolve::ratnz: NSolve was unable to solve the system with inexact coefficients. The answer was obtained by solving a corresponding exact system and numericizing the result. {{y -> (0.0001 (-966777. .b2 + 10000. r.b2))/.b2}}5.) I expected for y=-82,556Can anybody help me. Answer
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Posted 3 months ago
 You seem to be asking "If I have a circle with radius 10 centered at {-90, 27} what is its height at x=33.677. Put like that it should be pretty obvious that there will be no solution except for -100 Answer
Posted 3 months ago
 Hi Jon,. thank you for your answer. I found my mistake. The main problem was "²" is complitely different from "^2". Now my Problem is solved. But maybe you have an Idea how i can raise the decimal places of the x and y values. and can I calculate with these values (x or y)? Answer
Posted 3 months ago
 NSolve takes an option WorkingPrecision which lets you specify the number of decimal places to work to. It may also make sense to control the input precision of the real number with, say, 33.677`50 to pad it to 50 decimal places. Answer