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解方程组(1)2(x+y)-(x-y)=3①(x+y)-2(x-y)=1②(2)(x+2)^2-(y-3)^2=(x+y)(x-y)①x-3y=2②

题目详情
解方程组(1)2(x+y)-(x-y)=3① (x+y)-2(x-y)=1 ②
(2)(x+2)^2-(y-3)^2=(x+y)(x-y)① x-3y=2 ②
▼优质解答
答案和解析
x+y/2+x-y/3=1,4(x+y)-2(x-y)=1
设x+y=a x-y=b
∴a/2+b/3=1
3a+2b=6
4a-2b=1
解得:
a=1
b=3/2
∴x+y=1
x-y=3/2
∴x=5/4
y=-1/4