Answer:
After 3 seconds
Step-by-step explanation:
Given
[tex]h(t) = -5t^2 + 14t + 3[/tex]
Required
Time the drop will hit the ground
When the drop hits the ground,
[tex]h(t) = 0[/tex]
So, we have:
[tex]0 = -5t^2 + 14t + 3[/tex]
Rewrite as:
[tex]5t^2 - 14t - 3 = 0[/tex]
Expand
[tex]5t^2 + t - 15t - 3 = 0[/tex]
Factorize
[tex]t(5t + 1) -3(5t + 1) = 0[/tex]
Factor out 5t + 1
[tex](t -3)(5t + 1) = 0[/tex]
Split
[tex]t -3 = 0[/tex] or [tex]5t + 1 = 0[/tex]
Solve for t
[tex]t = 3[/tex] or [tex]5t = -1[/tex]
Time cannot be negative.
So:
[tex]t = 3[/tex]