Two equations will be called independent if their graphs touch only on one point (they have one solution for the x-value and one solution for the y-value), and two equations will be dependent if they touch at every point (there is an infinite number of solutions).
This definition of independent and dependent equations is shown in the following diagram. Consider that there are two lines, one red line and one blue line:
They are independent if they touch only on one point and dependent if they touch at every point (they are the same line).
In our case, we are asked to write an equation in order to create an independent consistent linear system.
Note: Consistent means that the system has a solution.
First, we graph the given equation:
There are many different equations that will form an independent consistent linear system with this equation.
We are going to choose the following line equation:
Because when we graph this equation next to the previous line:
We can see that they touch at one point, thus there is a solution and the system is independent --> we have created an independent consistent linear system.
what we don't know from the question is how big each of those 7 sections were. To form the equation we do this.
Since we know Sarah has 27 ft of pipe that would be our answer of the equation.
Sarah also removed 6 ft and the rest of the pipe she cut up into 7 small sections of equal length. since we don't know the length of the 7 smaller sections we will use the variable X to represent the length. this means that 6ft + 7x (X is the length of the pipes, and we multiply by 7 since there are 7 of them) must equal Sarah's total length of 27ft, therefore meaning our education would be
to solve for how long each pipe was, we need to solve for X by rearranging the equation as shown bellow.