1. The problem statement, all variables and given/known data A cannon is fired at a target on a cliff that is 400 meters away. The cliff has an elevation of 150 meters relative to the cannon. The initial velocity of the cannonball is 100 m/s. Ignoring wind resistance calculate the two possible angles and their respective times. X= 400m Y=150m V_naught=100m/s A= -9.81 m/s^2 2. Relevant equations Time X = Time Y X=V_naught*cos(theta)*t Y= V_naught*sin(theta)*t - 0.5*a(t)^2 1/(cos(theta)0^2=1+ (tan(theta))^2 3. The attempt at a solution t= 400/100cos(theta) 0= -0.5*a(t)^2 + V_naught*sin(theta)*t -150 0= -0.5*a(400/100cos(theta))^2 + V_naught*sin(theta)*400/100cos(theta) -150 I get stuck here. I'm not really quite sure what to do next. I'm pretty sure I have to use the quadratic equation, but don't know how.