化简(5a+7b-8c)^2-(5a+7b+8c)^2
{A+2B-3C=4,5A-6B+7C=8}求代数式A:B:C 2A-3C/A+2B
5a-{-3b+[6c-2a-(a-c)]}-[9a-(7b+c)]
已知a+b/a-b=b+c/2(b-c)=c+a/3(c-a),求证:8a+9b+5c=0
(a+b)/(a-b)=(b+c)/2(b-c)=(c+a)/3(c-a),abc互不相等,证8a+9b+5c=o
a←5 b←7 c←b-a b←a+b+c Print c/2 End
3(a+b-c)+8(a-b-c)-7(a+b-c)-4(a-b-c),其中b=2
1.计算5a/(6a^2c)-7b/(12ac^2)+11c/8a^2b
若a+2b-3c=4,5a-6b+7c=8,则9a+2b-5c=______.
若a/5=b/7=c/8,且3a-2b+c=3,则求2a+4b-3c=?
已知A/5=B/7=8/C,且3A-2B+C=3,求2A+4B-3C
若3a-2b=8,2b+3c=1,a+5c=7,则a=( ),b=( ),c=( )
已知(a+b)/2=(b-2c)/3=(3c-a)/4求(5a+6b-7c)/(8a9b)