a-8b=8 5a+4b=51
(2a+b)(a-b)=8 求a,b
(3a-6b)/(a+b) - (5a-6b)/(a-b) - (4a-5b)/(a+b) - (7a-8b)/(a-b
(3a-6b/a+b)-(5a-6b/a-b)-(4a-5b/a+b)-(7a-8b/b-a)
a+b+3(-a-b+1)=4(1-b-a)-5(b-1+a)求代数式7(a+b-3)/8-1的值
如果a-2b/a+2b=3,求a+2b/a-2b+3a-6b/4a+8b
(a-2b)/(a+2b)=3,求(a+2b)/(a-2b)+(3a-6b)/(4a+8b)的解,
3a^2b-{2a^2b+[9a^b-(6a^2b+4a^2)]-(3a^2b-8a^2)}=
已知|a|=6,|b|=8,且|a+b|=|a-b|,求|a-b|.
已知|a|=6 |b|=8,且|a+b|= |a-b| 求|a-b|
解方程组:9(a+b)+(a-b)=25,2(a+b)-(a-b)=8
a-2b/a+2b=3,求2+2b/a-2b+3a-6b/4a+8b的值
已知A=5a^3b+2a^4-3a^2b-ab^3,B=6ab^3-8a^3b+3a^4-5b^4,求2(2A+B)-3