posted by josephz .
A group of engineering students constructs a slingshot to launch water balloons. The angle of launch is 30° and the initial velocity of the balloon is 14 m/s. The students launch a balloon from the roof of a building and the balloon lands 42 m away from the building. How tall is the building?
use the formula
since it is on he roof,take y=-y=-H=height of the building
note: θ is not included in the exponent 2..just plug-in the value..
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