We are asked to determine the equation of a line that is perpendicular to the line:
[tex]y=-1[/tex]This is the equation of a horizontal line therefore a perpendicular line is a vertical line. Therefore, it must have the form:
[tex]x=k[/tex]The value of "k" is determined by a point "x" where the line passes. Since the line passes through the point (-5, 4), this means that the equation of the line is:
[tex]x=-5[/tex]And thus we have determined the equation of the perpendicular line.
