For this case, the first thing we must do is define variables.
We have then:
x: Maggie's age
y: Age of Maggie's brother
We write the system of equations that models the problem.
We have then:

We solve the system of equations.
For this, we use substitution:

From here, we clear the value of x:


Answer:
Maggie is 9 years old
Problem 1
With limits, you are looking to see what happens when x gets closer to some value. For example, as x gets closer to x = 2 (from the left and right side), then y is getting closer and closer to y = 1/2. Therefore the limiting value is 1/2
Another example: as x gets closer to x = 4 from the right hand side, the y value gets closer to y = 4. This y value is different if you approach x = 0 from the left side (y would approach y = 1/2)
Use examples like this and you'll get the results you see in "figure 1"
For any function values, you'll look for actual points on the graph. A point does not exist if there is an open circle. There is an open circle at x = 2 for instance, so that's why f(2) = UND. On the other hand, f(0) is defined and it is equal to 4 as the point (0,4) is on the function curve.
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Problem 2
This is basically an extension of problem 1. The same idea applies. See "figure 2" (in the attached images) for the answers.
Answer: 5
Step-by-step explanation: The coefficient is the number that comes right before the variable. Another way to say this is it's what the variable is multiplied by.
Answer:
B) 18.
Step-by-step explanation:
Add them up then divide by the amount of numbers there are.
Answer:
The Correct option is - d. all of the above.
Step-by-step explanation:
To find - In assessing the validity of any test of hypotheses, it is good practice to
a. examine the probability model that serves as a basis for the test by using exploratory data analysis on the data.
b. determine exactly how the study was conducted.
c. determine what assumptions the researchers made.
d. all of the above.
Proof -
All the Given options are correct to study the validity of a hypothesis test.
So,
The Correct option is - d. all of the above.