What Angle Should a Quarterback Throw to Hit a Stationary Receiver?

[Tensaiga]

Hello, there's my question.

A quarterback is running across the field, parallel to the line of scrimmage, at a constant speed of 2.5m/s, when he spots an open, stationary receiver straight downfield from him (ie, in a line parallel to the sidelines). If he can throw the football at a speed of 8.0m/s, relative to himself, at what angle, relative to the sidelines, must he throw it in order to hit the receiver? How far downfield was the receiver

I drew a diagram but i got 72 degress and 25m as the answer... but the correct answer should be 18 degrees and 23m. where did i go wrong?

i used tan = 8/2.5 and used that answer mutiplied by the velocity.

Thanks

Sorry i posted in the wrong place, just saw the head lines now...

 

[maverick280857]

Show us your work.

Hint: What is the velocity of the ball relative to the (static) ground.

 

[Tensaiga]

oh never mind i get it now = =

it's suppose to be Tan angle = 2.5/8
= 17.35 degrees

then C^2 = A^2 + B^2
= 22.80m
thanks~