i was wondering if i did this right

A cannon ball is shot from a cannon on top of a hill that is 73.5 meters above sea level. The cannon ball leaves the cannon with a velocity of 9.8 m/s. Write and solve a quadratic equation to determine when the cannon ball will reach sea level.

0 = -4.9t² + 9.8t + 73.5
0 = -4.9(t² - 2t - 15)
0 = -4.9(t - 5)(t + 3)
t - 5 = 0 and t + 3 = 0
t = {5,-3}

t = 5 since t = -3 is not acceptable negative value.

Hence, the cannon ball will reach sea level at 5 seconds.

1 answer

yes, assuming it was shot horizontally.