Another plan to secure the roller coaster involves placing two concrete struts on either side of the center of the leg of the roller coaster to add reinforcement against southerly winds in the region. Again, using the center of the half-circle as the origin, the struts are modeled by the equations and . A vertical reinforcement beam will extend from one strut to the other when the two cables are 2 feet apart.

Algebraically determine the x -value of where the beam should be placed.