Question

What equation passes through the point (3, 5) and is perpendicular to the line x = 4 A. y=5
B.x=5
C.y=4
D.x=3

Answer 1

\[x=4\]is a vertical line made up of all the points with an \(x\)-coordinate of \(4\).
To make a perpendicular line to a vertical line, you need a horizontal line, which can be written in the form \(y = k\) where \(k\) is a constant — this is the set of all points which have a \(y\)-coordinate equal to \(k\).

If you need your horizontal line to pass through the point \((3,5)\), what value of \(k\) do you need?