A water slide launches a child horizontally above a swimming pool. The distance from the top of the slide to the launch point is 2.76 m. The point where the child is launched horizontally is 0.7 m above the water. How far from the launch point does the child land in the water?

Answer 1

You need to know two things:
1. how long does it take to fall 0.7 m
2. How fast is your horizontal velocity after falling 2.76 meters?
Then
distance = horizontal velocity * time to fall 0.7 meters = u t
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so, how long to fall 0.7 m?
0.7 = (1/2) g t^2
t = sqrt (1.4/9.81)
then how fast is the child going?
(1/2) m u^2 = m g h
u = sqrt (2 g h) = sqrt (2*9.81*2.76)