# Plot an strange equation

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Nicholas on 27 Aug 2014
Answered: Nicholas on 27 Aug 2014
I have a big polynomial of the form:
f(x,y)=10.75-158.34*y+2112.07*y^2-12211.07*y^3-29.44*x+2185.91*x*y-35690.08*x*y^2+187137.42*x*y^3+129.16*x^2-9697.93*x^2*y+173834.73*x^2*y^2-935832.82*x^2*y^3-174.03*x^3+13191.71*x^3*y-245488.55*x^3*y^2+1384550.57*x^3*y^3
and I need to plot it for a specific solution, so if f(x,y)=8.5567 then I would need to plot:
8.5567=10.75-158.34*y+2112.07*y^2-12211.07*y^3-29.44*x+2185.91*x*y-35690.08*x*y^2+187137.42*x*y^3+129.16*x^2-9697.93*x^2*y+173834.73*x^2*y^2-935832.82*x^2*y^3-174.03*x^3+13191.71*x^3*y-245488.55*x^3*y^2+1384550.57*x^3*y^3
How can I do this? Any help would be greatly appreciated.
Thank you.
Nicholas.

David Sanchez on 27 Aug 2014
10.75-8.5567
ans =
2.1933
Then:
my_equation = '2.1933-158.34.*y+2112.07.*y.^2-12211.07.*y.^3-29.44.*x+2185.91.*x.*y-35690.08.*x.*y.^2+187137.42.*x.*y.^3+129.16.*x.^2-9697.93.*x.^2.*y+173834.73.*x.^2.*y.^2-935832.82.*x.^2.*y.^3-174.03.*x.^3+13191.71.*x.^3.*y-245488.55.*x.^3.*y.^2+1384550.57.*x.^3.*y.^3';
ezplot(my_equation,[-1 1 -1 1]); Nicholas on 27 Aug 2014
Thank you so very much!