Q:

On a vacation in Puerto Rico rose jumped off a cliff into a river in El Yunque go forest reserve her height as a function of time could be modeled by the function h(t) = -16tequals -16t ^2 + 16t + 480, where T is the time after jumping in seconds and H is the height in feet how many seconds did it take Rose to hit the water

Accepted Solution

A:
Answer: t = 6 sStep-by-step explanation: When Rose hit the water, the height of the jump is 0, so: h(t) = 0.Resolving it, we have:-16t² + 16t + 480 = 0To simplify the second degree equation, divided it by 16:-t² + t + 30 = 0Now, solve the equation using Bhaskara:Δ = 1² - 4. (-1) . 30Δ = 1 + 120Δ = 121t = [tex]\frac{-1+\sqrt{121} }{-2}[/tex]t₁ = [tex]\frac{-1 + 11}{-2}[/tex] = - 5t₂ = [tex]\frac{-11-11}{-2}[/tex] = 6Since time can be negative, it took t = 6s for Rose to hit the water.