(0,8) infinitely many solutions
Answer is:9x^2-12y^2-11x in other words D
Explanation: find all the common variables and combine. In this case since your adding adding you would add 8x^1 and x^2 to get 9x^ then add -9y^2 and -3y^2 to get -12y^2. And so on to get the rest of the problem. One tip to help make this simpler is circle one type of variable like circling all the x^2, boxing all the y^2, and underlining all the x. Hope this helps
Answer:
Option C
Step-by-step explanation:
The given inequality is
5x-1 < 19 and 
Group similar terms to get:
5x < 19+1 and 
5x < 20 and 
Solve for x to get:
x < 4 and 
The correct choice is C
Answer:
The 99% confidence interval for the average length of time all car owners plan to keep their cars is between 3.85 years and 10.55 years.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 7.2 - 3.35 = 3.85 years
The upper end of the interval is the sample mean added to M. So it is 7.2 + 3.35 = 10.55 years
The 99% confidence interval for the average length of time all car owners plan to keep their cars is between 3.85 years and 10.55 years.