104 = -16T2 + 729
16t^2 = 729 - 104 = 625
4t = +/-25
t = +/-6.25
Between 6.25 and 13.5 seconds after he jumps
P = [60] cm
Explanation:
6.5 cm + 6.5 cm + 7.5 cm + 7.5 cm + 7.5 cm + 7.5 cm + 8.5 cm + 8.5 cm
(y-4) (y-3)
you look at 12 and see what two factors of 12 add up to -7 and -4 times -3 is 12 and -4+-3 = -7