kakak yg bisa tlng bantu no 3 sampai 5.dibuat caranya

3) x + 5y = - 5 |×4
4x - 3y = 26
maka
4x + 20y = - 20
4x - 3y = 26
-----------------------(-)
23y = - 46
y = - 2
• x + 5y = - 5 |×3
4x - 3y = 26 |×5
maka
3x + 15y = - 15
20x - 15y = 130
-----------------------(+)
23x = 115
x = 5
hp = ( 5, - 2 )

4) 5x - 2y = 7 |×3
x - 3y = 4 |×2
maka
15x - 6y = 21
2x - 6y = 8
-------------------(-)
13x = 13
x = 1
subtitusi ke pers :
x - 3y = 4
1 - 3y = 4
- 3y = 4 - 1
- 3y = 3
y = - 1
hp = ( 1 , - 1 )

5) 3y = 4x - 9
4x - 3y = 9
2x + 5y = 11 |×2
maka
4x - 3y = 9
4x + 10y = 22
--------------------(-)
- 13y = - 13
y = 1
subtitusi
2x + 5y = 11
2x + 5(1) = 11
2x + 5 = 11
2x = 11 - 5
2x = 6
x = 3
hp = ( 3, 1 )