You have given a point coordinate. There are infinite equations that will have that solution. Remember, you need at least two points to define a line.
The most obvious set of equations with ##(4,-3)## as a solution would be
##x=4##
##y=-3##
If you want to restrict yourself to linear equations, you could use the slope-point form:
##y-(-3) = m(x-4)## for two (different) arbitrary values for ##m##, the slope.
for example
##m_1 = 2## and ##m_2 = 3##
would give equations
##y+3 = 2x-8##
or equivalently ##y=2x-11##
and
##y+3 = 3x-12##
or equivalently ##y=3x-15##
which together would have the required ##(4,-3)## solution.
