Write down the equation of each line shown in the diagram.

  

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$y=3$

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$x=3$

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$y=-1$

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$x=-1$

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$y=-3$

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$y=4$

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$x=\frac{1}{2}$

Draw the following graph on a pair of axes without plotting or drawing up a table of values.

$x=\frac{-7}{2}$