SOLUTION: I think this is the correct area for this, being as it has to do with graphs. I need help graphing a circle, but my graphing calculator refuses to let me equal the equation to 15 i

Algebra ->  Graphs -> SOLUTION: I think this is the correct area for this, being as it has to do with graphs. I need help graphing a circle, but my graphing calculator refuses to let me equal the equation to 15 i      Log On


   



Question 1042507: I think this is the correct area for this, being as it has to do with graphs. I need help graphing a circle, but my graphing calculator refuses to let me equal the equation to 15 instead of Y. Could anyone please explain how to graph this: x^2+y^2=15 ? I know it seems very simple, but I'm stuck!
Answer by ikleyn(52780) About Me  (Show Source):
You can put this solution on YOUR website!
.
I think this is the correct area for this, being as it has to do with graphs. I need help graphing a circle,
but my graphing calculator refuses to let me equal the equation to 15 instead of Y.
Could anyone please explain how to graph this: x^2+y^2=15 ? I know it seems very simple, but I'm stuck!
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x%5E2+%2B+y%5E2 = 15


is the circle with the center at the origin of a coordinate system with the radius r = sqrt%2815%29.

In general, if you have an equation %28x-h%29%5E2+%2B+%28y-k%29%5E2 = a, it desrcibes a circle with the center at the point (h,k) and the radius of sqrt%28a%29.

You can express y = sqrt%2815-x%5E2%29 from the equation.
May be, your calculator is able to plot these functions

y = sqrt%2815-x%5E2%29  and  y = -sqrt%2815-x%5E2%29,

that represent the upper and the lower parts of the circle?