What is a line perpendicular to x=7 that passes through (6,-9)?

Question

Please help. I am stuck and confused.

Answer 1

The line x = 7 is vertical.

So, the line that you are trying to find is horizontal and goes through the point (6,-9).

Horizontal lines have slope 0.

Equation of line: y - (-9) = 0(x - 6)

y = -9

Answer 2

x=7 line has slope of undefined as it doesn't passes through y axis. The perpendicular line will have slope of zero. That will be y= any number. since we were given that perpendicular line passes through (6,-9). We can use y co-ordinate from the point as number. That will give as number -9.

So the perpendicular line to X=7 , will be Y=-9.