2(x+y)-3(X-y)=3①4(X+y)+3(x-y)=15②_数学解答

2(x+y)-3(X-y)=3①4(X+y)+3(x-y)=15②

人气：393 ℃　时间：2020-09-05 06:22:13

解答

2(x+y)-3(X-y)=3 ① 4(X+y)+3(x-y)=15②
①+②得,
6(x+y)=18
x+y=6 ③
则x-y=[2(x+y)-3]/3=3 ④
③+④得,
2x=9
所以
x=9/2
y=6-x=3/2