(3x-y)(x+2y)最后等于多少!

来源:学生作业帮助网 编辑:六六作业网 时间:2025/01/25 01:46:47
(3x-y)(x+2y)最后等于多少!(3x-y)(x+2y)最后等于多少!(3x-y)(x+2y)最后等于多少!=3x²+6xy-xy-2y²=3x²+5xy-2y&#

(3x-y)(x+2y)最后等于多少!
(3x-y)(x+2y)最后等于多少!

(3x-y)(x+2y)最后等于多少!
=3x²+6xy-xy-2y²
=3x²+5xy-2y²

(3x-y)(x+2y)
=3x^2+6xy-xy-2y^2
=3x^2+5xy-2y^2

|3x-y+1|+(x+2y-3)的2次幂=0则3x-y+1=0①x+2y-3=0②①×2+②,得6x+2+x-3=0,解得x=1/7代入①,解得y=10/7