2x+3y=2007 2(3x-2y)-(x-y)+(-x+9y)等于多少

(1)2007的2次方减2006乘2008的值
=2007^2-(2007-1)(2007+1)
=2007^2-(2007^2-1)
=2007^2-2007^2+1
=1

(2)5a的2次方b乘(-34ac)
=5*(-34)a^2b*ac
=-170a^2b^2c

(3)a^m=2a^n=3
a^n=3/2
a^(2n+m)
=(a^n)^2*a^m
=(3/2)^2*3
=27/4

(4)(a的2次方)的3次方+a乘(-a)的5次方
=a^(2*3)+a(-a^5)
=a^6a^6
=0

(5)(-2x-3y)^2
=(2x+3y)^2
=4x^2+12xy+9y^2
=4x^2+kxy+9y^2
所以k=12

(6)20a^2b^4c/(-4a^3b^2)/ab
=20a^2b^4c/(-4a^4b^3)
=-5bc/a^2

(7)(2x+y)(3x+y)+(x+y)^2
=6x^2+5xy+y^2+x^2+2xy+y^2
=7x^2+7xy+2y^2

解：原式=6x-4y-x+y-x+9y
=4x+6y
=2×2007
=5004