To solve this using substitution you use what is given to you.
You have both the x and y, however you can choose which one you want to use.
If you choose to use y, then you’ll input the y equation into the x formula
x = 10 -2x -4
Then solve and continue as normal.
If you were to choose x, do the opposite.
y = 10 - 2(y - 4)
Hope this helps!
