Projectile: Find initial velocity without time

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JJBladester
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Homework Statement


Knowing that snow is discharged at an angle of 40 degrees, determine the initial speed, v0 of the snow at A. Answer: 6.98 m/s

Homework Equations



snow%20thrower.jpg


projectile.jpg


The Attempt at a Solution



I have found the x and y velocity and position formulas. Now since I don't know time, should I solve both position equations for time (t) and set them equal to each other to get my only unknown, vi? The quadratic equation for time in the y-dir seems a bit hectic. Is there an easier way to go about trying to find vi?
 
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kuruman said:
Start with
L = v0 t cosθ
Δy = v0 t sinθ - (1/2) g t2

Solve the first equation for t and replace in second equation. Solve the ensuing equation for v0.

I believe this is what you had in mind. The answer matches the professor's answer. Thanks again kuruman!

projectile%20final.jpg