p = -4
q could be 6.5 units to the right ... or to the left ... of point p.
to the right: p + q ⇒ [tex]-4 + (6\frac{1}{2}) = 2\frac{1}{2}[/tex]
to the left: p - q ⇒ [tex]-4 - (6\frac{1}{2}) = -10\frac{1}{2}[/tex]
Answer: [tex]2\frac{1}{2}[/tex] or [tex]-10\frac{1}{2}[/tex]