7x+2y=4 x= y= 4x-3y=23

问题描述:

7x+2y=4 x= y= 4x-3y=23

7x+2y=4 (1)
4x-3y=23 (2)
(1)*3+(2)*2得:
29x=58
x=2
代入(1)解得:y=-5