Answer
The curve bulges to the right for $c \lt -1$.
The curve represents a straight line for $c=-1$.
The curve bulges to the left for $-1\lt c \lt 0$.
We can observe a cusp for $c=0$.
The curve is a loop fo $c \gt 0$.
All curves have the vertical asympototes $x=1$.
Work Step by Step
The noteworthy points about the curves are following:
The curve bulges to the right for $c \lt -1$.
The curve represents a straight line for $c=-1$.
The curve bulges to the left for $-1\lt c \lt 0$.
We can observe a cusp for $c=0$.
The curve is a loop fo $c \gt 0$.
All curves have the vertical asympototes $x=1$.
