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.
You multiply pi times 3m which equals 9.42
Translate to english and i can help
1. x
2. x + 2
3. x + 4
x + 4 + 2x = 25. Second option is the answer.
Combine like terms
3x + 4 = 25
Subtract 4 from both sides
3x = 21
Divide both sides by 3
x = 7
