Related rates: a camera televising the opening kickoff of a football game is positioned 5 yards from the east edge of the field and in line with the goal line. the player with the football runs down the east edge of the field (just in bounds) for a touchdown. when he is 10 yards from the goal line, the camera is turning 0.4 rad/sec. how fast is the player running. i know that the professor wants a diagram with a formula, then you take the derivative of that and plug in your information to find the answer, however, i can not figure out the diagram.

Check the picture below.

now, hmmm I notice the came angle rate is positive,.... meaning the camera angle is increasing, no decreasing, therefore is really turning away from the goal line, meaning the runner is not going towards the goal line, but moving away from it, was wondering, if the runner is going to the goal line, the 0.4 rad/sec should be negative, but anyway, is not.

keeping in mind that, "x" distance of 5 yards, is a constant, whilst "y" is not, and neither is the angle.





which ends up at 10.

make sure your calculator is in Radian mode, since the angle is in radians.