Chapter 3 - Parallel and Perpendicular Lines - 3-7 Equations of Lines in the Coordinate Plane - Practice and Problem-Solving Exercises - Page 194: 37

The equation of the horizontal line that passes through this point is $y = 4$. The equation of the vertical line that passes through this point is $x = 6$.

We are given the point $(6, 4)$. If a horizontal line passes through the given point, then each point on that line would have a y-coordinate of $4$; therefore, the equation of the horizontal line that passes through this point is $y = 4$. If a vertical line passes through the given point, then each point on that line would have an x-coordinate of $6$; therefore, the equation of the vertical line that passes through this point is $x = 6$.