Answer: FIRST OPTION.
Step-by-step explanation:
First, it is important to remember that the Slope-Intercept form of the equation of a line is the shown below:

Where "m" is the slope of the line and "b" is the y-intercept.
By definiton, given a System of Linear equations, if they are exactly the same line, then the System of equations have Infinely many solutions.
In this case you have the following System of Linear equations given in the exercise:

So, since you need the system has Infinite solutions, you know that the slope and the y-intercept of both lines must be equal.
Therefore, you can identify that the value of "a" and "b" must be the following:

So the Linear System would be the shown below:

Answer:
Step-by-step explanation:
Commission =2.5% of 8000

= $ 200
The formula for calculating the simple interest is given by

Here, P = Principle amount
r = annual interest rate in decimal
t = time in years.
Now, if we invest for months or week then in order to find the simple interest, we must convert the units in years.
Therefore, d is the correct option.
d) Interest rates are annual, so you must convert the units into years.
For this case we have that each student takes 8 \ frac {3} {4} minutes to perform and play 3 songs. Then, we convert the mixed number to a fraction:

Thus, each student takes
minutes.
If there are 9 students in the recital then we have:
minutes.
Thus, the recital lasts at least 78.75 minutes.
Answer:
The recital lasts at least 78.75 minutes.