Answer:
after 11.07secs
Step-by-step explanation:
Given the height of an object modeled by the equation
H = 16T² - 1960
The height of the object on the surface of water is zero, hence H = 0
Substitute
0 =16T² - 1960
Swap
16T² - 1960 = 0
16T² = 1960
T² = 1960/16
T² = 122.5
T = 11.07
Hence the rock will hit the surface of the water after 11.07secs
12
x/2+4=10
-4 -4
________
x/2=6
(2/1)*(x/2)=(2/1)*(6)
x=12
Rational!
The decimal is terminating so this is rational.
10 cm i think
but i dont know.
