Polynomial equation involving gamma function $\Gamma(x)$

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I'm quite new to the world of special functions.

Recently for research purposes, I've arrived to the following equation:

$$\Gamma(x) = 20(5x+1),$$

with $x \in \mathbb{R}$.

I've tried to exploit the fact that $\Gamma(x) = (x-1)!$ for integer $x$, and I found that $x=7$ is a solution.

Anyway, I've arrived to this solution just by plugging iteratively integer numbers into the equation. I'm wondering if there is a calculus approach which can be used to find also non-integer solutions, if any, for problem in the form

$$\Gamma(x) = p(x),$$

where $p(x)$ is a polynomial.

For the proposed problem, I've found numerically that also $x \simeq -0.24$ is a solution