If an object is propelled upward from a height of s feet at an initial velocity of v feet per second, then its height h after t seconds is given by the equation h=-16t^2+vt+s, where h is in feet. If the object is propelled from a height of 8 feet with an initial velocity of 64 feet per second, its height h is given by the equation h=-16t^2+64t+8.
After how many seconds is the height 36 feet?

Question

If an object is propelled upward from a height of s feet at an initial velocity of v feet per second, then its height h after t seconds is given by the equation h=-16t^2+vt+s, where h is in feet. If the object is propelled from a height of 8 feet with an initial velocity of 64 feet per second, its height h is given by the equation h=-16t^2+64t+8.
 After how many seconds is the height 36 feet?