So first you need to factor and get 8( t-1 ) (2t+1)=0. Then you need to divide both sides by 8 to isolate the equation. 0/8=0 so ( t-1 ) (2t+1)=0. Next set each of the factors = to 0 and get t-1=0 and 2t+1=0. Solve, and get t=1 and t=-1/2. The negative does not apply so you know it takes 1 second for the ball to hit the ground.
