# How to display the symbolic form of an equation?

I have this problem. I want to show the unassessed form of the equations that I enter in the graph, however, every equation that I introduce results in the substitution of the known values within the equation.

a*x^2 + 2*y + 1 -> 5*x^2 + 2*y + 1


where a = 5

Manipulate[a = 5;
Grid[
{
{"Equation", Row[{u, " = 0"}]},
{Plot3D[u, {x, -5, 5}, {y, -5, 5}]}
}, Alignment -> Left],
{{u, a*x^2 + 2*y + 1, "Equation"}},
BaseStyle -> Directive[FontSize -> 16, FontFamily -> "Optima"]]


I have tried with {"Equation", Row[{HoldForm[u], " = 0"}]}, but it did not work.

• But it will only work for that case and not for any other equation that you write when you run the Manipulate. – Tomás Valencia May 21 at 3:59

Here is a workaround:

Clear[a]
Manipulate[
aa = 5;
Grid[{{TraditionalForm[u]}, {"Equation", Row[{u, " = 0"}]},
{Plot3D[u /. a -> aa, {x, -5, 5}, {y, -5, 5}]}},
Alignment -> Left],
{{u, a*x^2 + 2*y + 1, "Equation"}},
BaseStyle -> Directive[FontSize -> 16, FontFamily -> "Optima"]]


• Works correctly. A suitable solution. – Tomás Valencia May 21 at 18:36