What you want to do is take that path SOUTH to White Rock Lake. You can do a few laps around the lake ~10miles per lap

You can see the concrete path just west of the intersection of Park Central Dr. and Banner Dr.

That concrete path will lead you south to the cycling mecca of DFW. It is best to go clockwise around the lake because there is some construction on the west side.

The loop around the lake is pretty much W. Lawther Rd. and E. Lawther Rd. Some open to traffic, some not. here is my run route from my old house, its similar. You enter the trail near the intersection of W. Lawther and Mockinbird. Where the concrete path dumps you off.
http://www.sanoodi.com/route/fpugsley/37539/once-around-wrl/