Answer:
Step-by-step explanation:Since we want to know how much time elapsed since the object was launched until it ht the ground. At the ground, the height is 0.
Therefore the equation h(t) = 80t – 16t2 becomes 0= 80t – 16t2
Solving the equation for t gives 80t =16t2 or 16t=80 or t=5sec
The object hits the ground 5 seconds after it is launched.
Answer:
If 3 students walked, then according to the given ratios, 18 students would have taken the bus.
Step-by-step explanation:
Given: 3 Walkers
1:2 --> 3:6 walkers to subway
1:3 --> 6:18 subway to bus riders
3. 140 m^3
(3 x 6 x 7) + (1 x 2 x 7) = 126 + 14 = 140
4. 216 in^3
(4 x 4 x 9) + (3 x 4 x 6) = 144 + 72 = 216