The line should be perpendicular to x = -4
x= -4 is a vertical line crossing the x axis at x= -4
The slope is undefined in x =-4
For an equation in slope intercept form, the general form is ;
y= mx + b where m is the slope and b is the y-intercept
So for any y value, x is always -4
Thus the slope for line x = -4 is not defined
A line perpendicular to x = -4 will thus be a horizontal line with slope 0
For the equation of this line
0= y--5/x-4
0 = y+5 /x-4
0{x-4} = y +5
0 = y+5
y= - 5