PLEASE HELP...My motor B for my fountain , is -16x^2+210x-690 , How many seconds does it take for the water from this motor to return to the ground? the x- intercept is -210/-16 ?? help please

Question

anonymous · Answer

graph it and the x value at the second zero is the answer for how many seconds it takes

anonymous · Answer

i dont understand,

anonymous · Answer

isnt there only one zero on graphs ?

anonymous · Answer

no no..when you graph it, itll be a parabola...so it intersects the x axis twice...the second intersection is the answer :)

anonymous · Answer

ok can you give me a minute to do that and you check it for me ?

anonymous · Answer

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anonymous · Answer

yea sure...graph it on a graphing calculator

anonymous · Answer

is it 13 ?

anonymous · Answer

wait doesnt 13 tell when it hits the ground again ? what about when its is in the air ? @yummydum

anonymous · Answer

isnt that what you need to find...how long it takes to hit the ground again?

anonymous · Answer

well i need that to so thank you but no, this is the question... in order to synchronize the neighboring fountain head to begin as soon as this one returns to the ground, you need to determine the time the water from this motor is in the air.

anonymous · Answer

@yummydum

anonymous · Answer

ohhhhh :// someone please helppppp !

anonymous · Answer

i have that same question