X = 6Y - 1
2X - 10Y = 3
-----------------
2*( 6Y - 1) - 10Y = 3
12Y - 2 - 10Y = 3
2Y = 5
Y = 2,5
X = 15 - 1 = 14
===================================
5X + Y = 4
X + Y - 6 = 0
---------------
Y = 4 - 5X
X + 4 - 5X - 6 = 0
-4X - 2 = 0
4X = - 2
X = - 0,5
Y = 4 + 2,5 = 6,5
===================================
12X - 3Y = 5
6Y - 24X = - 10
----------------
6Y - 24X = - 10
- 6Y + 24X = 10
---------------
0 = 0
Любые значения переменных Х и Y