Respuesta :
Answer:
It will take 1.19 seconds for the ball to hit the ground if no other players touch it
Step-by-step explanation:
The height of the ball after t seconds is given by the following equation:
[tex]h(t) = -4.9t^{2} + 5t + 1[/tex]
How long will it take the ball to hit the ground if no other players touch it?
This is t when h(t) = 0. So
[tex]-4.9t^{2} + 5t + 1 = 0[/tex]
Solving a quadratic equation:
Given a second order polynomial expressed by the following equation:
[tex]ax^{2} + bx + c, a\neq0[/tex].
This polynomial has roots [tex]x_{1}, x_{2}[/tex] such that [tex]ax^{2} + bx + c = a(x - x_{1})*(x - x_{2})[/tex], given by the following formulas:
[tex]x_{1} = \frac{-b + \sqrt{\bigtriangleup}}{2*a}[/tex]
[tex]x_{2} = \frac{-b - \sqrt{\bigtriangleup}}{2*a}[/tex]
[tex]\bigtriangleup = b^{2} - 4ac[/tex]
In this question:
[tex]-4.9t^{2} + 5t + 1 = 0[/tex]
So [tex]a = -4.9, b = 5, c = 1[/tex]
So
[tex]\bigtriangleup = 5^{2} - 4*4.9*1 = 44.6[/tex]
[tex]t_{1} = \frac{-5 + \sqrt{44.6}}{2*(-4.9)} = -0.17[/tex]
[tex]t_{2} = \frac{-5 - \sqrt{44.6}{2*(-4.9)} = 1.19[/tex]
Since we want a time measure, the answer cannot be negative.
It will take 1.19 seconds for the ball to hit the ground if no other players touch it