M-2n = 8
n = m - 2
The value of m in the system of equations is:

m= -4

Step 1: Substitute information

To solve this we will use the substitution method. This means that we will use the information provided to us in the second equation, and substitute it into the first equation. We are told what n equals, so let’s substitute this now.

m-2n=8
m-2(m-2)=8

Step 2: Distribute

Now that we have substituted the information, let’s distribute. This means that we will multiply the numbers on the outside of the parentheses with the numbers on the inside of the parentheses. Let’s do this now.

m-2(m-2)=8
m-2m+4=8

Step 3: Combine like terms

Now that we have distributed, we can continue solving the problem. The next step is to combine like terms. This means to combine terms with the same variable, or lack of. In this case, that is m and -2m.

m-2m+4=8
-m+4=8

Step 4: Get variable alone on the left side

We can now work to get the variable alone on the left side. We can do this by moving the number on the right side, in this case by adding 4 on both sides.

-m+4=8
-m=4

Step 5: Make m positive

In this final step, we must work to make m positive. We can do this by multiplying each term by -1. This will make m positive, and 4 negative. Let’s do this now.

-m=4
-1(-m)= -1(4)
m= -4

This is your answer! M is equal to -4. Hope this helps! Comment below for more questions.