Yeah, I pretty much spent 5 hours today trying to figure this question out, yet for some reason I keep getting the wrong answer. I told my friends I'd do it and explain it to them, but I still can't do it right. Can some one please show me the steps using only the letters, not just numbers. Thanx. A projectile is launched into the air from the top of an incline that makes an angle f =39° with the horizontal as show in the diagram below. The launch speed, v, is known to be 10.0 m/s but the launch angle, q, is unknown. However, the maximum height above the launch level that the projectile reaches is known to be h = 2.51 m. The trajectory is a perfectly parabolic. What is the angle, a (in degrees), with which the projectile strikes the incline (measured relative to the incline as shown)? Use g = 9.80 m/s2. http://koso.champlaincollege.qc.ca/moodle/file.php/85/q5_4ProjectileOnIncline.png (I dunno if the picture works, but give it a shot) 2. Relevant equations Basic Motion Equations Vf = Vi + A(D)T (D)X = Vi(D)T + (A(D)T^2)/2 Vf^2 = Vi^2 + 2A(D)X (D) is Delta I know Calculus, but my friends don't yet. (I would right down one of my attempt, but it would take way too long!) I understand how you're supposed to do it(break it up horizontally and vertically) and whatever else(ex: hor. vel. doesn't change, but vert. does due to gravity), but for some reason all the things I tried never gave me the right answer. I filled nearly five pages of stuff! Basically, I seperated the problem into four points each with their x and y values(position, velocity, acceleration) and the change in time at each one. Using the 3 equations I'm able to find all the other data, but for some reason I keep messing up no matter what way I do it. I'm certain that q = arcsin(((root)2AH)/10), but I mess u psomewhere along the line. So yeah, any help would be great.