Rutba

a firecracker is fired from the ground. The height of the firecracker at a given time is modeled by the function h(t) =-5t^2+50t, where h(t) is the height in metres and t is the time in seconds. When will the firecracker reach a height of 45m ?

A 5.0 m tree is leaning 5° from the vertical. To prevent it from leaning any farther, a stake needs to be fastened 2 m from the top of the tree at an angle of 60°with the ground. How far from the base of the tree, to the nearest metre, must the stake be?