早教吧 育儿知识 作业答案 考试题库 百科 知识分享

解方程组:{(x+2)^2-(y-3)^2=(x+y)(x-y){x-3y=2

题目详情
解方程组:{(x+2)^2-(y-3)^2=(x+y)(x-y) { x-3y=2
▼优质解答
答案和解析
(x+2)^2-(y-3)^2=(x+y)(x-y) .(1)
x-3y=2 .(2)
由(1)得:
x²+4x+4-y²+6y-9=x²-y²
4x+6y=5 .(3)
(2)*2+(3):
2x+4x = 4+5
6x=9
x=3/2
代入(2)得:
3/2-3y=2
3-6y=4
66=-1
y=-1/6