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1. The problem statement, all variables and given/known data

I can't believe how much time I have spent on this.

2. Relevant equations

Constant acceleration

3. The attempt at a solution

Here is the data I am using to solve for

[itex]V_a[/itex]

[itex]x_0=0[/itex],

[itex]x_f=30[/itex],

[itex]y_0=7[/itex],

[itex]y_f=10[/itex],

[itex]a_y=-g=-32.2[/itex],

[itex]V_{0y}=V_a\sin30[/itex],

[itex]V_{0x}=V_a\cos30[/itex]

From x direction:

[tex]\Delta X=V_{0x}t\Rightarrow t=\frac{30}{V_a\cos30}[/tex]

From y direction:

[tex]\Delta Y=V_{oy}+.5a_yt^2[/tex]

[tex]\Rightarrow 3= V_a\sin30*(\frac{30}{V_a\cos30})-16.1[\frac{30}{V_a\cos30}]^2[/tex]

[tex]\Rightarrow 3=30\tan30-16.1*(\frac{40}{V_a})^2[/tex]

Which gets me a negative under the radical!

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# Homework Help: Projectile motion (am I on drugs?)

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