Reputation: 1130
I have a circle with the expression:
x^2+y^2+10x-14y-7=0
I need to find the radius and the coordinates to the center of the circle using Wolfram Mathematica; in Symbolab it tells me to rewrite the expression in the form of the standard eclipse equation.
I know that the answer should be c=(x+5)^2 + (y-7)^2 = 81, so the radius is sqrt(81) = 9 ...
How is this achievable in Mathematica (I'm very new to this...)?
Thanks and best regards (-:
Upvotes: 0
Views: 317
Reputation: 6989
Solve[{
CoefficientList[x^2 + y^2 + 10 x - 14 y - 7, {x, y}]
==
CoefficientList[(x - xc)^2 + (y - yc)^2 - r^2, {x, y} ],r>0}
, {xc, yc, r}]
{{xc -> -5, yc -> 7, r -> 9}}
Upvotes: 0
Reputation: 25703
For example,
SolveAlways[{x^2 + y^2 + 10 x - 14 y - 7 == (x - a)^2 + (y - b)^2 - r^2}, {x, y}]
Upvotes: 2