Question

Can you help mw with my work?

Answer 1

In this problem the function that models the hight is:

`h(t)=-5t^2+14t+3`

So when the water hits the grownd h=0 so we replace that and solve for t so:

`0=-5t^2+4t+3`

To solve this expression we can use the cuadratic equation:

`x=\frac{-4\pm\sqrt[]{16-4(-5)(3)}}{-10}`

and we operate so:

`\begin{gathered} x=\frac{-4\pm\sqrt[]{76}}{-10} \\ x=(-4\pm8.7)/(-10) \end{gathered}`

Now we solve bout of the equation so:

`\begin{gathered} x_1=(-4+8.7)/(-10)=-0.47 \\ x_2=(-4-8.7)/(-10)=1.27_{} \end{gathered}`

So the answer that have sense is the secon one so the water hits the ground after 1.27 seconds