Answer:
Step-by-step explanation:
The given system is:
Since I prefer to use smaller numbers I'm going to divide both sides of the first equation by 3 and both sides of the equation equation by 6.
This gives me the system:
We could solve the first equation for 
and replace the second with that.
Let's do that.
Subtract 
on both sides:
So we are replacing the second in the second equation with 
which gives us:
Now recall the first equation we arranged so that was the subject. I'm referring to .
We can now find given that using the equation .
Let's do that.
with :
So the solution is (8,-1).
We can check this point by plugging it into both equations.
If both equations render true for that point, then we have verify the solution.
Let's try it.
with 
:
is a true equation so the "solution" looks promising still.
with :
is also true so the solution has been verified since both equations render true for that point.
Answer:
Step-by-step explanation:
a) Sample statistics are used to estimate population value. Since 48% is a sample proportion, therefore, it is a sample statistic.
b) For 95% confidence level, z* = 1.96.
\hat{p}\pm z^* \sqrt{\frac{\hat{p}(1-\hat{p})}{n}}= 0.61\pm 0.61\sqrt{\frac{0.61(1-0.61)}{1578}}=0.61\pm 0.024 \ or (0.586, 0.634).
We are 95% confident that the true proportion of US residents who think marijuana should be made legal lies between 58.6% and 63.4%.
c)
\\np=1578(0.61)=962.58
\\n(1-p)=1578(1-0.61)=615.42
Since both np and n(1-p), are at least 10, the normal model is a good approximation for these data.
d) As the lower limit of confidence interval is less than 0.5, less than 50% population is also a plausible value of true proportion. This means the statement "Majority of Americans think marijuana should be legalized" is not justified.
Answer:
A, C, E
Step-by-step explanation:
From the table you can see that the water depth cahnges
for every
of snow (option B is false).
This means that the function modelling this situation is linear function (option A is true and option D is false). Let the equation of this function be 
Then
Subtract these two equations:
Hence,
The equation of the straight line (the graph of linear function) is 
(option E is true) This line passes through the point (0,0), because its coordinates satisfy the equation (option C is true).
Answer: An error was made! All correlation coefficients: -1 ≤ r ≤ 1.
Rectangle:
4*8=32
Semicircle:
3.14*4^2= 50.24
50.24/2=25.12
Add:
25.12+32= 57.12
Final answer: A
