8x-10=3x+90
5x=100
X=20
B=3(20)+90=150
H (t) = - 16t ^ 2 + 16t + 480
For this case, the first thing to do is to match the polynomial to zero to find the roots.
We have then:
0 = -16t ^ 2 + 16t + 480
From here, we obtain the following roots of the polynomial:
t1 = -5
t2 = 6
We ignore the negative root because the time is always greater than zero.
Answer:
it takes Rose to hit the water about
t = 6 seconds