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Well, athe "naïve" answer could be based on the fact(already implied in @Somnium's comment) is that a general method for finding the solutions of a system of simultaneous polynomial equations $$ f_1(x)=0, \ \ f_2(x)=0, \ \ \cdots \ \ f_n(x)=0 $$ is finding the $\gcd\bigl(f_1, f_2, \cdots, f_n\bigr)=g(x)$, of these polynomials.:

Assuming that we are speaking about polynomials with complex coefficients and since $\mathbb{C}[x]$ is a PID, the ideal of $\mathbb{C}[x]$ generated by the polynomials $f_1, f_2, \dotsc, f_n$ is the ideal generated by their greatest common divisor: $$ \langle f_1, f_2, \dotsc, f_n\rangle=\langle\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)\rangle=\langle g\rangle. $$

Thus, the solution of the initial system, is equivalent to the solution of the single equation $$ g(x)=0. $$

And well, ok maybeMaybe there is no explicit formula for the gcd of a number of univariate polynomials (in terms of their coefficients) but there is certainly an algorithm: The $\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)$, can be found using the Euclidean division algorithm for finding the $\gcd$ of two univariate polynomials in $\mathbb{C}[x]$ together with the fact that for $n\geq 3$ $$ \gcd(f_1, f_2, \dotsc, f_n)=\gcd\bigl(f_1,\gcd(f_2, \dotsc, f_n)\bigr). $$

P.S.: I am not sure if this satisfies you as an answer but I was led to this description driven by the way the question has been posed and the subsequent discussion in the comments.

Well, a "naïve" answer could be based on the fact that a general method for finding the solutions of a system of simultaneous polynomial equations $$ f_1(x)=0, \ \ f_2(x)=0, \ \ \cdots \ \ f_n(x)=0 $$ is finding the $\gcd\bigl(f_1, f_2, \cdots, f_n\bigr)=g(x)$, of these polynomials.

Assuming that we are speaking about polynomials with complex coefficients and since $\mathbb{C}[x]$ is a PID, the ideal of $\mathbb{C}[x]$ generated by the polynomials $f_1, f_2, \dotsc, f_n$ is the ideal generated by their greatest common divisor: $$ \langle f_1, f_2, \dotsc, f_n\rangle=\langle\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)\rangle=\langle g\rangle. $$

Thus, the solution of the initial system, is equivalent to the solution of the single equation $$ g(x)=0. $$

And well, ok maybe there is no explicit formula for the gcd of a number of univariate polynomials but there is certainly an algorithm: The $\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)$, can be found using the Euclidean division algorithm for finding the $\gcd$ of two univariate polynomials in $\mathbb{C}[x]$ together with the fact that for $n\geq 3$ $$ \gcd(f_1, f_2, \dotsc, f_n)=\gcd\bigl(f_1,\gcd(f_2, \dotsc, f_n)\bigr). $$

P.S.: I am not sure if this satisfies you as an answer but I was led to this description driven by the way the question has been posed and the subsequent discussion in the comments.

Well, the "naïve" answer (already implied in @Somnium's comment) is that a general method for finding the solutions of a system of simultaneous polynomial equations $$ f_1(x)=0, \ \ f_2(x)=0, \ \ \cdots \ \ f_n(x)=0 $$ is finding the $\gcd\bigl(f_1, f_2, \cdots, f_n\bigr)=g(x)$, of these polynomials:

Assuming that we are speaking about polynomials with complex coefficients and since $\mathbb{C}[x]$ is a PID, the ideal of $\mathbb{C}[x]$ generated by the polynomials $f_1, f_2, \dotsc, f_n$ is the ideal generated by their greatest common divisor: $$ \langle f_1, f_2, \dotsc, f_n\rangle=\langle\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)\rangle=\langle g\rangle. $$

Thus, the solution of the initial system, is equivalent to the solution of the single equation $$ g(x)=0. $$

Maybe there is no explicit formula for the gcd of a number of univariate polynomials (in terms of their coefficients) but there is certainly an algorithm: The $\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)$, can be found using the Euclidean division algorithm for finding the $\gcd$ of two univariate polynomials in $\mathbb{C}[x]$ together with the fact that for $n\geq 3$ $$ \gcd(f_1, f_2, \dotsc, f_n)=\gcd\bigl(f_1,\gcd(f_2, \dotsc, f_n)\bigr). $$

P.S.: I am not sure if this satisfies you as an answer but I was led to this description driven by the way the question has been posed and the subsequent discussion in the comments.

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Well, a "naive""naïve" answer could be based on the fact that a general method for finding the solutions of a system of simultaneous polynomial equations $$ f_1(x)=0, \ \ f_2(x)=0, \ \ ... \ \ f_n(x)=0 $$$$ f_1(x)=0, \ \ f_2(x)=0, \ \ \cdots \ \ f_n(x)=0 $$ is finding the $\gcd\big(f_1, f_2, ..., f_n\big)=g(x)$$\gcd\bigl(f_1, f_2, \cdots, f_n\bigr)=g(x)$, of these polynomials.

Assuming that we are speaking about polynomials with complex coefficients and since $\mathbb{C}[x]$ is a PID, the ideal of $\mathbb{C}[x]$ generated by the polynomials $f_1, f_2, ..., f_n$$f_1, f_2, \dotsc, f_n$ is the ideal generated by their greatest common divisor: $$ <f_1, f_2, ..., f_n>=<\gcd\big(f_1, f_2, ..., f_n\big)>=<g> $$$$ \langle f_1, f_2, \dotsc, f_n\rangle=\langle\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)\rangle=\langle g\rangle. $$

Thus, the solution of the initial system, is equivalent to the solution of the single equation $$ g(x)=0 $$$$ g(x)=0. $$

And well, ok maybe there is no explicit formula for the gcd of a number of univariate polynomials but there is certainly an algorithm: The $\gcd\big(f_1, f_2, ..., f_n\big)$$\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)$, can be found using the Euclidean division algorithm for finding the $\gcd$ of two univariate polynomials in $\mathbb{C}[x]$ together with the fact that for $n\geq 3$ $$ \gcd(f_1, f_2, ..., f_n)=\gcd\big(f_1,\gcd(f_2, ..., f_n)\big) $$$$ \gcd(f_1, f_2, \dotsc, f_n)=\gcd\bigl(f_1,\gcd(f_2, \dotsc, f_n)\bigr). $$

P.S.: I am not sure if this satisfies you as an answer but iI was led to this description driven by the way the question has been posed and the subsequent discussion in the comments.

Well, a "naive" answer could be based on the fact that a general method for finding the solutions of a system of simultaneous polynomial equations $$ f_1(x)=0, \ \ f_2(x)=0, \ \ ... \ \ f_n(x)=0 $$ is finding the $\gcd\big(f_1, f_2, ..., f_n\big)=g(x)$, of these polynomials.

Assuming that we are speaking about polynomials with complex coefficients and since $\mathbb{C}[x]$ is a PID, the ideal of $\mathbb{C}[x]$ generated by the polynomials $f_1, f_2, ..., f_n$ is the ideal generated by their greatest common divisor: $$ <f_1, f_2, ..., f_n>=<\gcd\big(f_1, f_2, ..., f_n\big)>=<g> $$

Thus, the solution of the initial system, is equivalent to the solution of the single equation $$ g(x)=0 $$

And well, ok maybe there is no explicit formula for the gcd of a number of univariate polynomials but there is certainly an algorithm: The $\gcd\big(f_1, f_2, ..., f_n\big)$, can be found using the Euclidean division algorithm for finding the $\gcd$ of two univariate polynomials in $\mathbb{C}[x]$ together with the fact that for $n\geq 3$ $$ \gcd(f_1, f_2, ..., f_n)=\gcd\big(f_1,\gcd(f_2, ..., f_n)\big) $$

P.S.: I am not sure if this satisfies you as an answer but i was led to this description driven by the way the question has been posed and the subsequent discussion in the comments.

Well, a "naïve" answer could be based on the fact that a general method for finding the solutions of a system of simultaneous polynomial equations $$ f_1(x)=0, \ \ f_2(x)=0, \ \ \cdots \ \ f_n(x)=0 $$ is finding the $\gcd\bigl(f_1, f_2, \cdots, f_n\bigr)=g(x)$, of these polynomials.

Assuming that we are speaking about polynomials with complex coefficients and since $\mathbb{C}[x]$ is a PID, the ideal of $\mathbb{C}[x]$ generated by the polynomials $f_1, f_2, \dotsc, f_n$ is the ideal generated by their greatest common divisor: $$ \langle f_1, f_2, \dotsc, f_n\rangle=\langle\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)\rangle=\langle g\rangle. $$

Thus, the solution of the initial system, is equivalent to the solution of the single equation $$ g(x)=0. $$

And well, ok maybe there is no explicit formula for the gcd of a number of univariate polynomials but there is certainly an algorithm: The $\gcd\bigl(f_1, f_2, \dotsc, f_n\bigr)$, can be found using the Euclidean division algorithm for finding the $\gcd$ of two univariate polynomials in $\mathbb{C}[x]$ together with the fact that for $n\geq 3$ $$ \gcd(f_1, f_2, \dotsc, f_n)=\gcd\bigl(f_1,\gcd(f_2, \dotsc, f_n)\bigr). $$

P.S.: I am not sure if this satisfies you as an answer but I was led to this description driven by the way the question has been posed and the subsequent discussion in the comments.

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Well, a "naive" answer could be based on the fact that a general method for finding the solutions of a system of simultaneous polynomial equations $$ f_1(x)=0, \ \ f_2(x)=0, \ \ ... \ \ f_n(x)=0 $$ is finding the $\gcd\big(f_1, f_2, ..., f_n\big)=g(x)$, of these polynomials.

Assuming that we are speaking about polynomials with complex coefficients and since $\mathbb{C}[x]$ is a PID, the ideal of $\mathbb{C}[x]$ generated by the polynomials $f_1, f_2, ..., f_n$ is the ideal generated by their greatest common divisor: $$ <f_1, f_2, ..., f_n>=<\gcd\big(f_1, f_2, ..., f_n\big)>=<g> $$

Thus, the solution of the initial system, is equivalent to the solution of the single equation $$ g(x)=0 $$

And well, ok maybe there is no explicit formula for the gcd of a number of univariate polynomials but there is certainly an algorithm: The $\gcd\big(f_1, f_2, ..., f_n\big)$, can be found using the Euclidean division algorithm for finding the $\gcd$ of two univariate polynomials in $\mathbb{C}[x]$ together with the fact that for $n\geq 3$ $$ \gcd(f_1, f_2, ..., f_n)=\gcd\big(f_1,\gcd(f_2, ..., f_n)\big) $$

P.S.: I am not sure if this satisfies you as an answer but i was led to this description driven by the way the question has been posed and the subsequent discussion in the comments.