Answer:
(-3,-12)
Step-by-step explanation:
Multiply the first equation by three to match the second equations y-term
The y-terms cancel out
Add the x-terms with each other and the terms after the equal sign as well
Divide -57 by 19
Input your x-term (-3) into one of the two first equations and multiply
Either:
Simplify your terms
Divide
Answer:
The triangle formula is always base times height divided by 2 I forgot the circle formula
Step-by-step explanation:
Answer:
We need to sample at least 1069 parents.
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.
How many parents do you have to sample?
We need to sample at least n parents.
n is found when 
. So
Rounding up
We need to sample at least 1069 parents.
You would multiply 18 machines x 16" for a total of 288 inches. You would then divide by 36 because there are 36" (or 3 feet) in a yard. The answer is 8 yards of tubing.
