Answer:
Step-by-step explanation:
Answer: There are 3 even numbers on the cube. There are 2 sides to a coin. there is a 1/2 chance of the cube landing on an even number. There is a 1/2 chance of the coin landing on tails.
There is a 1/4 chance of these events occurring together.
Answer:
It takes 2.8 seconds for the ball to fall 215 ft.
Step-by-step explanation:
We are given a position function s(t) where s stands for the number of feet the ball has fallen, so we have to replace s with the given value of 215 ft and solve for the time t.
Setting up the equation.
The motion equation is given by
![s(t) =16t^2+32t](https://tex.z-dn.net/?f=s%28t%29%20%3D16t%5E2%2B32t)
We can replace there s = 215 ft to get
![215=16t^2+32t](https://tex.z-dn.net/?f=215%3D16t%5E2%2B32t)
Solving for the time t.
From the previous equation we can move all terms in one side to get
![16t^2+32t-215=0](https://tex.z-dn.net/?f=16t%5E2%2B32t-215%3D0)
At this point we can solve for t using quadratic formula.
![t = \cfrac{-b\pm \sqrt{b^2-4ac}}{2a}](https://tex.z-dn.net/?f=t%20%3D%20%5Ccfrac%7B-b%5Cpm%20%5Csqrt%7Bb%5E2-4ac%7D%7D%7B2a%7D)
where a, b and c are the coefficients of the quadratic equation
![at^2+bt+c=0](https://tex.z-dn.net/?f=at%5E2%2Bbt%2Bc%3D0)
So we get
![a=16\\b=32\\c=-215](https://tex.z-dn.net/?f=a%3D16%5C%5Cb%3D32%5C%5Cc%3D-215)
Replacing on the quadratic formula we get
![t = \cfrac{-32\pm \sqrt{32^2-4(16)(-215)}}{2(16)}](https://tex.z-dn.net/?f=t%20%3D%20%5Ccfrac%7B-32%5Cpm%20%5Csqrt%7B32%5E2-4%2816%29%28-215%29%7D%7D%7B2%2816%29%7D)
Using a calculator we get
![t=-4.8 , t = 2.8](https://tex.z-dn.net/?f=t%3D-4.8%20%2C%20t%20%3D%202.8)
Physically speaking the only result that makes sense is to move forward in time that give us t = 2.8 seconds.
We can conclude that it takes 2.8 seconds for the ball to fall 215 ft.