x + 2y = 8 4x - 2y = 12 --------------------- Add 5x = 20 etc. ------
x + 2y = 8_____x = 8 - 2y ------ eq (i)
4x - 2y = 12 ----- eq (ii)
To use substitution, just solve ONE of the 2 equations for a variable that has 1 as its coefficient, as seen above
4(8 - 2y) - 2y = 12 ------ Substituting 8 - 2y for x in eq (ii)
32 - 8y - 2y = 12
- 10y = 20
Now, substitute 2 for y in eq (i) to find the value of x
That's ALL!! Nothing COMPLEX!