Answer:

Step-by-step explanation:
Using the rule of exponents
×
=
, then
×
=
= 
Answer: 0.0775
Step-by-step explanation:
Given : Mean : 
Standard deviation : 
Sample size : 
Since its normal distribution , then the formula to calculate the z-score is given by :-

For x= 28.2 hours

For x= 30 hours

The P- value = 

Hence, the probabiliy that the average time spent stydying for the sampe was between 28.2 and 30 hours = 0.0775
First, put your polynomial in standard form(ax²+bx+c=0). Then plug the a,b and c for x=(-b+-√b²-4ac)÷2a. As a result, you can either get one, two or no real answers.
Set up your parentheses, and put x in the front of both because x is squared. It should look like this: (x )(x ). Next, you find notice that one sign must be positive, and one must be negative. Then, you find the factors of 36. 6 and 6, 3 and 12, 1 and 36, 18 and 2, and 9 and 4. You then guess and check with the different signs and factors what will get you back to the trinomial using the FOIL method. When you do this, you should get (x-9)(x+4).