for which equation is (5,1215) a solution

$${\mathtt{4}}{\mathtt{\,\times\,}}{{\mathtt{x}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{115.162\: \!049}} = {\mathtt{0}} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = {\mathtt{\,-\,}}{\frac{{\mathtt{11\,243}}}{{\mathtt{2\,000}}}}\\ {\mathtt{x}} = {\frac{{\mathtt{10\,243}}}{{\mathtt{2\,000}}}}\\ \end{array} \right\} \Rightarrow \left\{ \begin{array}{l}{\mathtt{x}} = -{\mathtt{5.621\: \!5}}\\ {\mathtt{x}} = {\mathtt{5.121\: \!5}}\\ \end{array} \right\}$$

Well if that is a decimal point in the question then you answer is definitely correct. :)

Thanks Einstein.

an easier answer might have been 

x-0.1215=5     

4x²+2x-115.162049=0