Amanda is practing her dives off the diving board. When she dives into the water the path her body makes and where she resurfaces can be modeled by the equation 0=x^2-8x+7 where x is the number of horizontal feet she travels. Find the number of feet she will travel when she returns to the surface

Every weekday, mr. jones bikes from his home to his job. sometimes he rides along two roads, the long route that is shown by the solid lines. other times, he takes the shortcut shown by the dashed line. how many fewer kilometers does mr. jones bike when he takes the shortcut instead of the long route?