V = d/t = 8.8 miles/[80/60] hours = 6.6 miles/hour
t = d/v = d/6.6
Answer: d/6.6, where d is the number of miles to run.
I think it’s D because the only thing that happen was that they rotated so I think it’s D but if it’s wrong sorry
Let
be the unknown number. So, three times that number means
, and the square of the number is 
We have to sum 528 and three times the number, so we have 
Then, we have to subtract this number from
, so we have

The result is 120, so the equation is

This is a quadratic equation, i.e. an equation like
. These equation can be solved - assuming they have a solution - with the following formula

If you plug the values from your equation, you have

So, the two solutions would be


But we know that x is positive, so we only accept the solution 
Operations that can be applied to a matrix in the process of Gauss Jordan elimination are :
replacing the row with twice that row
replacing a row with the sum of that row and another row
swapping rows
Step-by-step explanation:
Gauss-Jordan Elimination is a matrix based way used to solve linear equations or to find inverse of a matrix.
The elimentary row(or column) operations that can be used are:
1. Swap any two rows(or colums)
2. Add or subtract scalar multiple of one row(column) to another row(column)
as is done in replacing a row with sum of that row and another row.
3. Multiply any row (or column) entirely by a non zero scalar as is done in replacing the row with twice the row, here scalar used = 2
The answer is going to be 5 laps per day because I did 15 laps/3days and divided each side by 3 which the answer is going to be 5/1 but it’s basically 5 since it’s going to be a whole number in this set. Therefore the unit rate of 15 laps in 3 days is going to be 5 laps per day.