Given, vertex: (5,4) focus (-5,4).
Since the y coordinates of the vertex and the focus are the same, the focus and the vertex are on the same horizontal line, y=4. So,the axis of symmetry is a horizontal line.
SInce vertex: (5,4) and focus (-5,4), we find that the focus is at the left of the vertex. So, the parabola opens leftwards.
So, the equation of parabola is,
![\begin{gathered} (y-k)^2=4a(x-h) \\ \text{Here, vertex(}h,k)=(5,4) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/yn6nrdpwfu7e6j99m1hmb6kj9plv0eapsx.png)
a=-5-(5)=-10 , since y coordinates are same.
Now, above equation becomes,
![\begin{gathered} (y-4)^2=4*(-10)(x-5) \\ (y-4)^2=-40(x-5) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/78bbevs61948o6e6zkj02ayjco1vy3od1v.png)
So, the equation of the parabola is,
![\begin{gathered} \\ (y-4)^2=-40(x-5) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/ko1m99mq1fdcpd3vdsiy7ptw3urxvadrki.png)