Answer:
1.95secs
Step-by-step explanation:
Given the height of the float expressed as h(t) = -16t2 - 3t + 55.
The floats reach the swimmer at h(t) = 0
Substitute
0 = -16t^2 - 3t + 55.
16t^2 + 3t - 55 = 0
Using the general formula;
t = -3±√3²-4(16)(-55)/2(16)
t = 3±√9+3520/32
t = 3±√3529/32
t = 3+59.41/32
t = 62.41/32
t = 1.95
Hence it will take 1.95secs
