Part 1:
For this case we must see in the graph the axis of symmetry of the given parabola.
We have then that the axis of symmetry is the vertical line t = 2.
Answer:
The height of the javelin above the ground is symmetric about the line t = 2 seconds:
Part 2:
For this case, we must see the time t for which the javelin reaches a height of 20 feet for the first time.
We then have that when evaluating t = 1, the function is h (1) = 20. To do this, just look at the graph.
Then, we must observe the moment when it returns to be 20 feet above the ground.
For this, observing the graph we see that:
h (3) = 20 feet
Therefore, a height of 20 feet is again reached in 3 seconds.
Answer:
The javelin is 20 feet above the ground for the first time at t = 1 second and again at t = 3 seconds
Answer:
0.04326
Step-by-step explanation:
The answer is 28 years
At = A0 * e^(-k * t)
At = 12 g
A0 = 15 g
k = 7.9 × 10^-3 = 0.0079
t = ?
12 = 15 * e^(-0.0079 * t)
12/15 = e^(-0.0079 * t)
0.8 = e^(-0.0079 * t)
Logarithm both sides (because ln(e) = 1:
ln(0.8) = ln(e^(-0.0079 * t))
ln(0.8) = (-0.0079 * t) * ln(e)
-0.223 = -0.0079 * t
t = -0.223 / -0.0079
t = 28.23
t ≈ 28 years
Answer:
the value is k=
Step-by-step explanation: