A water balloon is 5 feet above the ground when Sally launches it into the air. Use the quadratic equation 0 = -t2 + 4t + 5 to find how much time, t, it takes for the water balloon to reach the ground.

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Answer:

2-sqrt14/2, 2+sqrt13/2.

Step-by-step explanation:

What you do is you have to do the quadratic equation like it says in the problem.

x=  −b± sqrtb^2 −4ac /2a .

a=-2, b=4, c=5.

x=-4±sqrt(4)^2-4(-2)(5)/2(-2).

x=-4±sqrt16+40/-4.

x=-4±2sqrt14/-2.

2-sqrt14/2, 2+sqrt13/2. is your answer once you have done everything.

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Answer:

5 seconds

Step-by-step explanation:

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