# Projectile motion of a baseball

hey, i'm having some difficulty with this problem.
A baseball player makes perfect contact with the ball, striking it 45 degrees above the horizontal at a point 1.3m above the ground. his homerun hit just clears the 3.0m wall 130m from home plate. with what velocity did the baseball player strike the ball?
Code:
  /
/                                                            |
[U]/ ) 45     [/U]                                                   |
|                                                         | 3.0m
| 1.3m                                                    |
|[U]                                                         |             [/U]
130m
this is pritty much what i have. i have no clue where to start. i've been trying to figure it out but no success... :(

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uh...i did...i did lyk..30 questions on projectile motion...i know how to do the questions. i'm just stuck on this question.

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Were you not given a value for time between the ball being hit and it clearing the wall?

(Although you may not need it for this question)

ok...i am pretty sure i can help you witht his one :)
if you have been learning projectile motion in class then you should know:
$$\Delta Y = (V_{0}sin\varphi)(t)-.5gt^{2}$$
where $$\varphi = 45 degrees (the angle of "launch"$$
also you should know:
$$\Delta X = (V_{0}cos\varphi)(t)$$

NOW here is what you will have to do:
solve the change in X function for t and plug that in for wherever "t" appears in the change in Y equation
set the change in Y to equal 1.7 m (the ball needs to at least hit that point to make it over the wall) and then solve that big nasty equation algebraically to get $$\ (V_{0}$$

***edit : sorry its my first time with the math code so ill write this out
phi = 45 cuz its the angle of launch (the writing was kinda hard to read)