Respuesta :

Answer:

7 seconds, 6 seconds

Step-by-step explanation:

a) For the object to reach the ground, the height from the ground has to be 0. therefore, let the function h = 0

0 = -16t^2 + 700

the amswers are + or - 6.61

we cant have negative time so it is approximately 7 seconds.

b) for the object to reach a 100 feet, h =100

100 = -16t^2 + 700

0 = -16t^2 + 600

solve: + or - 6.12

therefore it takes approximately 6 seconds to reach 100 feet.