Foci: and 7. A track goes around a football field. The inner part of the track is 140 yd on its longest axis. -70 70 The goal posts, representing the foci, are 120 yd apart. The starting lines are located on the -60 60 co-vertices of the inner track. Find the equation of the ellipse representing the inner track. How far are the starting lines from the center of the field? 8. A student examines an ellipse with foci of (43, 0) and (-43, 0) and with vertices of (45, 0) and (-45, 0). He claims that the ellipse has co-vertices of (0, 44) and (0, -44). Is the student correct? Explain. enVision TM Algebra 2 . Teaching Resources