Using a system of equation, we have that:
a)
- x, which is the cost of on-site service.
- y, which is the cost of at-store service.
- z, which is the cost of by-mail service.
b)
The system is:



c)
The cost of one on-site repair service is of $90.
Item a:
The variables are:
- x, which is the cost of on-site service.
- y, which is the cost of at-store service.
- z, which is the cost of by-mail service.
Item b:
On-site service costs <u>3 times as much as at-store service</u>, thus:

By mail service costs <u>$10 less than at-store</u> service, thus:

Last week, the shop completed <u>15 services on-site, 40 services at-store, and 5 services by mail for total sales of $3100</u>, thus:

The system is:



Item c:
- The cost of one on-site repair service is x.
- First, replacing the first two equations into the third, we find y, and then with it we find x.






Then

The cost of one on-site repair service is of $90.
A similar problem is given at brainly.com/question/24823220
Answer:
Step-by-step explanation:
Let's simplify step-by-step.
2x−y
There are no like terms.
Answer:
=2x−y
Remember that the slope of a line never changes, so you can choose whatever 2 points you want and you will always get the same slope. Calculate the rise and run (You can draw it on the graph if it helps). The slope is 2/4, which , of course, you can simplify to ½.
Answer: Use employee identification numbers to randomly select 200 employees
Step-by-step explanation:
Random sampling refers to a sampling technique whereby each sample has an equal chance of being selected. It is an unbiased representation of the entire population and this is vital in drawing conclusion.
From the options given, the best way to randomly choose these 200 employees will be to use employee identification numbers to randomly select 200 employees.