求一道代数式的值已知a-2b/a+2b=53（a-2b）/5（a+2b）+2（a+2b）/a-2b

Question

求一道代数式的值
已知a-2b/a+2b=5
3（a-2b）/5（a+2b）+2（a+2b）/a-2b

Answer 1

(a+2b)/(a-2b)=1/5
原式=3/5×（a-2b)/(a+2b)+2×(a+2b)/(a-2b)
=3/5×5+2×1/5
=3+2/5
=17/5