Answer: Second option.
Explanation:
The equation of the line in Slope-Intercept form is:

Where "m" is the slope and "b" is the y-intercept.
It is important to remember the following:
1- The slopes of parallel lines are equal.
2- The slopes of perpendicular lines are negative reciprocal.
Then, given the first equation:

You can identify that:

The second equation is:

Solve for "y":

You can identify that:

Then, since the slopes are negative reciprocal, you can conclude that the lines for the given pair of equations are perpendicular.