Answer:
y = - 9
Explanation:
x = 7 is the equation of a vertical line parallel to the y- axis and passing through all points with an x- coordinate of 7
A line perpendicular to it is a horizontal line parallel to the x- axis with equation y = c
Where c is the value of the y- coordinates the line passes through.
The line passes through (5, - 9) with y- coordinate - 9, thus
equation of line is y = - 9