The rock that hits the ground first will be the one with lowest time that is rock B
Given the height of Rock A by the function f, where f(t) = 4 + 30t – 16t^2
Also, for the rock B, the function g(t) = 5 + 20t – 16t^2
The rock will hit the ground at f(t) = g(t) = 0
Substituting the values into the function, we will have:
4 + 30t – 16t^2 = 0
On factorizing the time taken to reach the ground is 2secs
For the function g(t) = 5 + 20t – 16t^2
0= 5 + 20t – 16t^2
On factorizing the time taken to reach the ground is 0.625secs
Hence the rock that hits the ground first will be the one with lowest time that is rock B
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