5x-4y= 17 ②

①*5-②*3:

15x-35y- 15x+ 12y = 5-5 1

-23y=-46

y=2

Give y=2 generations and get: 3x- 14= 1 x=5.

∴x=5

y=2

23x+ 17y=63 ①

17x+23y=57 ②

①× 17-②×23:23 * 17x+ 17 * 17y- 17 * 23x-23 * 23y = 63 * 17-57 * 23。

17? y-23？ y = 107 1- 13 1 1

y( 17-23)( 17+23)=-240

-240y=-240

y= 1

Take y= 1 generation ①: 23x+ 17=63.

23x=46

x=2

∴x=2

y= 1

2x+y=6 ①

x+2y=3 ②

①-②×2: 2x+y-2x-4y=6-6。

y=0

Take y=0 and get 2x=6 from the first generation.

∴x=3

y=0

y=2x-3 ①

3x+2y=8 ②

From ① generation ②, 3x+4x-6=8 is obtained.

7x= 14

x=2

Take x=2 generations and get: y=4-3= 1.

∴x=2

y= 1