Answer:
-1/12
Step-by-step explanation:
make the denominators congruent
8/12 and 9/12
then subtract
-1/12
Answer:
5(x-1)
Step-by-step explanation:
1.

2.

3. -7/30
4. i believe it is the communitive of multiplication , but not 100% sure
Answer:

Step-by-step explanation:
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The t distribution or Student’s t-distribution is a "probability distribution that is used to estimate population parameters when the sample size is small (n<30) or when the population variance is unknown".
The shape of the t distribution is determined by its degrees of freedom and when the degrees of freedom increase the t distirbution becomes a normal distribution approximately.
Data given
Confidence =0.99 or 99%
represent the significance level
n =16 represent the sample size
We don't know the population deviation 
Solution for the problem
For this case since we don't know the population deviation and our sample size is <30 we can't use the normal distribution. We neeed to use on this case the t distribution, first we need to calculate the degrees of freedom given by:

We know that
so then
and we can find on the t distribution with 15 degrees of freedom a value that accumulates 0.005 of the area on the left tail. We can use the following excel code to find it:
"=T.INV(0.005;15)" and we got
on this case since the distribution is symmetric we know that the other critical value is 
Answer:
Neither
Step-by-step explanation:
The slopes are not opposite and they are not equal either
line up 2x+3y=42 and -3x +2y=16
2x+3y=42=-3x+2y=16
get each term on one side and isolate.
If this is not possible, you have your answer. Another way to do this is graphing it and seeing if the two lines intersect, and if they do, if they make a right angle