Solving Long Jump: Find Take-Off Speed

[PhysicsCCR]

Homework Statement

An athlete executing a long jump leaves the ground at a 29.6° angle and travels 7.43 m. What was the take-off speed?

I have 4 unknown variables: t, initial velocity in the x direction (Vix), initial velocity in the y direction (Viy). and the initial speed which I'm trying to find (Vi).

Which kinematic equations do I use? I've been stuck on this problem for a day now.

 

[BruceW]

It depends on what they mean by 'travels 7.43m'... They probably mean his horizontal displacement is 7.43m when he hits the ground. I'm going to assume this is the case.

Have you done similar questions before? what kind of motion can we assume this guy has while he is in the air?