Question

How do you find the equation of the line perpendicular to the line `y=5` and passing through `(5, 4)`?

Answer 1

Since the graph of `y=5` is a horizontal line, any line perpendicular to a horizontal line is a vertical line, whose equation can be written in the form `x=a`. Since it passes through the point `(5,4)`, so the equation is:

`x=5`

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I hope that this was helpful.