a projectile is launched upward from a platform 60 feet in the air. if its initial velocity is 68 feet per second, its distance above its starting point t seconds after it is launched can be modeled using the quadratic equation: d(t) = -16t^2 + 68t + 60. after how many seconds does the projectile hit the ground?

Question

a projectile is launched upward from a platform 60 feet in the air. if its initial velocity is 68 feet per second, its distance above its starting point  t seconds after it is launched can be modeled using the quadratic equation: d(t) = -16t^2 + 68t + 60.  after how many seconds does the projectile hit the ground?

goformit100 · Answer

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anonymous · Answer

If u want "t"should to know we have 2 answer .
To find t in a quadratic equation we first use this :
Delta=b^2-4ac
Then use Delta in this :
-b^2+_ $$sqrt{Delta}$$/2a=X1&Xx2
In this question we have :
a=-16
b=68
c=60
Now can u answer to your self ?!