![y=-2x^2-12x+3](https://img.qammunity.org/2023/formulas/mathematics/college/yldckh6km5op5uw5h89zbi4iz0gyrvhldi.png)
This equation has the form:
![y=ax^2+bx+c](https://img.qammunity.org/2023/formulas/mathematics/high-school/g7mvpjunjwe6qob7ddy7l4f0glbtdi9gci.png)
with a = -2, b = -12, and c = 3
The x-coordinate of the vertex is found as follows:
![\begin{gathered} x_V=(-b)/(2a) \\ x_V=(-(-12))/(2\cdot(-2)) \\ x_V=(12)/(-4) \\ x_V=-3 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/1qagm03gzyguhpnmf8xsm47jcb3x642fw2.png)
The y-coordinate of the vertex is found replacing the x-coordinate into the equation:
![\begin{gathered} y_V=-2x^2_V-12x_V+3 \\ y_V=-2(-3)^2-12\cdot(-3)+3 \\ y_V=-18+36+3 \\ y_V=21 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/4fbuw7cdim0jqhnklji03dztdkcqrhv67z.png)
vertex: (-3, 21)
The axis of symmetry is:
![\begin{gathered} x=x_V \\ x=-3 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/2aski0vysro4fl36jkrpcc5lkogwlmwuzv.png)
Given that a is negative, then the vertex is a maximum