How to solve systems of equation

Well its easy mean search a video in YouTube

there are two types for systems of question:

The method for elimination

The method for substitution

The elimination only that u have to do is found x or y hat are the sam, e number with different symbols ↓↓like this↓↓

- 7y + 3x = 45

7y + 12x = 33

the y is cancel and ... u know the process ...

But the method for substitution is different u only need to put the y en the problem and that's it, and when u found the valor of x u can solve for y ↓↓like this↓↓

4x - 2y = 24

y = x - 5

4 (x - 5) = 24

4x - 20 = 24

+20 + 20

4x = 44

4x/4 = 44/4

x = 11