Angle Relationship Between Intersecting Lines

In a plane, lines $l_1$ and $l_2$ intersect at point $P$. The measure of angle $ heta$ formed by line $l_1$ is 45 degrees. If line $l_2$ is perpendicular to line $l_1$, what is the measure of the angle that line $l_2$ forms with the positive x-axis?

To visualize, imagine line $l_1$ extending to the right from point $P$, making a 45-degree angle with the positive x-axis. Line $l_2$ intersects line $l_1$ and extends upwards from point $P$.