[tex]\bf \textit{ vertex of a vertical parabola, using coefficients}\\\\
\begin{array}{lcccll}
y = &{{ -5}}x^2&{{ +30}}x&{{ -25}}\\
&\uparrow &\uparrow &\uparrow \\
&a&b&c
\end{array}\qquad
\left(-\cfrac{{{ b}}}{2{{ a}}}\quad ,\quad {{ c}}-\cfrac{{{ b}}^2}{4{{ a}}}\right)[/tex]
