已知(3a-b)/(2b-a)=7,(x+y)/(2x-y)=5,求(ax-2by)/(ax+2by)的值.
<p>问题:已知(3a-b)/(2b-a)=7,(x+y)/(2x-y)=5,求(ax-2by)/(ax+2by)的值.<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">马凤英的回答:<div class="content-b">网友采纳 (3a-b)/(2b-a)=7 3a-b=14b-7a 10a=15b a=3b/2 (x+y)/(2x-y)=5 x+y=10x-5y 9x=6y ∴x=2y/3 ∴ax=3b/2×2y/3=by ∴(ax-2by)/(ax+2by) =(by-2by)/(by+2by) =-1/3
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