Answer:
<em>Thus, the dimensions of the metal plate are 10 dm and 8 dm.</em>
Step-by-step explanation:
For a quadratic equation:

The sum of the roots is -b and the product is c. Note the leading coefficient is 1.
We know the perimeter of the rectangular metal plate is 36 dm and its area is 80 dm^2. Being L and W its dimensions, then:
P=2(L+W)=36
A=L.W=80
Note both formulas are closely related to the roots of the quadratic equation, we only need to adjust the data for the perimeter to be exactly the sum of L+W and not double of it.
Thus we use the semi perimeter instead as P/2=L+W=18
The quadratic equation is, then:

Factoring by finding two numbers that add up to 18 and have a product of 80:

The solutions to the equation are:
x=10, x=8
Thus, the dimensions of the metal plate are 10 dm and 8 dm.
Answer:
10
Step-by-step explanation:
1 is 8, 2 is 6, 3 is 4, and 4 is 2. The pattern is -2, so to get it when x=0 you just add 2 to 8
Answer: e. test for a difference in two population means
Step-by-step explanation:
Since the researcher takes a random sample of patients and measures their cholesterol levels before and after a treatment cycle of the drug, then the two samples are matched pairs. The difference between both samples would be determined and the mean and standard deviation of this difference is calculated. This would be used to determine the test statistic.
Therefore, the type of hypothesis test that they should use is
e. test for a difference in two population means