All methods are supposed to be correct in most if not all situations and it should not matter if you use a different method given the options
The answer you are looking for is c
Answer:
D. y = (x - 3)²
Step-by-step explanation:
The parabola formula in vertex form is:
y = a(x - h)² + k
where the vertex is located at (h, k). Replacing with vertex (3, 0) we get:
y = a(x - 3)² + 0
y = a(x - 3)²
In all possible options the leading coefficient <em>a</em> is equal to one. Therefore:
y = (x - 3)²
1) Type of motion: constant acceleration.
2) acceleration, a = 9.8 m/s^2
3) time up = time down = 4seconds / 2 = 2 seconds
4) formula = Vf = Vo - a*t^2/2
Vf = 0 => Vo = a*t^2 / 2 = 9.8m/s^2 * (2 s)^2 / 2 = 19.6 m/s
Answer: 19.6 m/s