The top base is 3, so the coordinates of the fourth point are (3,4).
The answer is (A).
SLOPE-INTERCEPT FORM
With    the topic   of  slope-intercept form,   we  move    from    coordinate  geometry    that    is  primarily
geometric   into    coordinate  geometry    that    is  primarily   algebraic.  Slopes  and intercepts  are
descriptions    of  lines   and points  on  the grid,   but the processes   of  finding and/or  using   slopes  and/or
intercepts  are generally   algebraic   processes.  There’s no  need,   for instance,   to  sketch  a   diagram for a
question    like    Example 3.
SLOPE-INTERCEPT FORM
For any equation    in  the form    y   =   mx  +   b:Example 3m   =   slope
b   =   y-intercept1. Which    of  the following   lines   has no  point   of  intersection    with    the line    (A)