Question

daca a/b =2/7 , calculati valoarea raportului 3a-b supra 2a+b

Answer 1

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Answer 2

a/b=2/7=k=>a=2k și b=7k
(3a-b)/(2a+b)=(3*2k-7k)/(2*2k+7k)=(6k-7k)(4k+7k)=-k/11k=-1/11

sau

a/b=2/7=>a=2b/7
(3a-b)/(2a+b)=(3*2b/7-b)/(2*2b/7+b)=(6b/7-b)/(4b/7+b)=(6b/7-7b/7)(4b/7+7b/7)=(-b/7)/(11b/7)=-b/7*7/11b=-1/11