Question

A bullet fired up 1120 feet per second at the height of 8 feet. Use the formula to determine how many seconds it will take to hit the ground. Round to 2 decimal places It will take _ seconds

Answer 1

The bullet will take 70.00 seconds to hit the ground

Explanation:

`\begin{gathered} \text{Given the modeled equation } \\ h=-16t^2\text{ }+v_ot\text{ + 8} \\ \text{where h = height} \\ v_o\text{ = initial velocity} \\ h\text{ = 8 ft} \\ v_o\text{ = 1120 ft/sec} \\ \text{Substitute the above values into the modeled equation} \\ 8=-16t^2\text{ + 1120(t) + 8} \\ 8=-16t^2\text{ + 1120t + 8} \\ \text{Collect the like terms} \\ 8-8=-16t^2\text{ + 1120t} \\ 0=-16t^2\text{ + 1120t} \\ 16t^2\text{ = 1120t} \\ -16t^2\text{ + 1120t = 0} \\ \text{factorize out 16t} \\ -16t(t\text{ - 70) = 0} \\ -16t\text{ = 0 or t - 70 = 0} \\ t\text{ = 0 or t = 70} \\ \text{Hence, t is 70.00 seconds} \end{gathered}`