Write an equation of the following line:
a line perpendicular to x - 2y + 3 = 0 and passing through the point (4;-1)
thse slope of this line is
now the equation of the line passing through (4,-1) is:
; where m is the slope.
these two lines are perpendicular if the product of their slopes is -1, that is,
find m and fit it in the second equation to find the equation of the line.