I going to ask my question in another way, and excuse me for my English. My question is

` H1[x_, y_]=(d x + w y) + 2(c x - a y)/d + y^2 a^2 `

I need to chose values for those five parameters for some reason, then, for example, I choose them like

`S1 = {b -> -1.2, c -> 0.1, d -> 4, a -> - 0.8, w -> 2} `

When I try to search for the intersection values of `H1`

with the `y`

axis

`Solve[(H1[0, y] /. S1) == -0.5, y] (*{{y -> -3.52859}, {y -> -0.221405}}*) y1 = -3.5285945694153686; y2 = -0.22140543058463089; Solve[(H1[0, y] /. S1) == -1, y] (*{{y -> -3.27254}, {y -> -0.477458}}*) y3 = -3.272542485937368; y4 = -0.4774575140626314; `

now I have

`H2[x_, y_] = (-1 + 4 (c1 + b1 y)^2 - 2 (1 + x α1 + γ1)^3 + a1 x + y β1)/(c1 + b1 y)^3 `

another function with six new parameters, i need to find these parameters by solving the system

`eq1 = Numerator[Factor[H2[0, y1] - H2[0, y2]]] eq2 = Numerator[Factor[H2[0, y3] - H2[0, y4]]] `

This system is with inexact parameters

`Sol = Solve[({eq1, eq2} /. {b1 -> 1, γ1 -> 0.5}) == 0, {β1, c1}, Reals] `

When i use `Solve`

, it’s giving me a solution of the same system but with inexact coefficients. My problem is when I try to solve this system

`e1=H1[0, y]-H1[0, Y] e2=H2[0, y]-H2[0, Y] `

I need to find the same results of `y1`

, `y2`

, `y3`

and `y4`

, but since `Solve`

uses exact parameters, I don’t find the same results. I need a solution, please, thank you.