Vertical angles are formed when two lines intersect, creating two pairs of opposite angles. Each angle in a pair of vertical angles is equal to the other.
To determine which angle is a vertical angle with ∠5, you would need a visual representation of the angles and their relationships (often seen in a diagram of intersecting lines).
If you have a diagram, look for the angle directly opposite ∠5. That angle will be its vertical angle. If you provide more context or a description of the diagram, I can help identify the vertical angle corresponding to ∠5.