Question

[Vũ Hằng Ngân]

Bài toán:Tìm x

2/3 : x/5 + 5/7 = 2/7 : 3/5 + 10/9

Giúp mik nha m.n

Answer 1

[Triệu Mẫn]

\(\frac{2}{3}:\frac{x}{5}+\frac{5}{7}=\frac{2}{7}:\frac{3}{5}+\frac{10}{9}\)

\(\frac{2}{3}:\frac{x}{5}+\frac{5}{7}=\frac{10}{21}+\frac{10}{9}\)

\(\frac{2}{3}:\frac{x}{5}+\frac{5}{7}=\frac{100}{63}\)

\(\frac{2}{3}:\frac{x}{5}\)        \(=\frac{100}{63}-\frac{5}{7}\)

\(\frac{2}{3}:\frac{x}{5}\)       \(=\frac{55}{63}\)

      \(\frac{x}{5}\)       \(=\frac{2}{3}:\frac{55}{63}\)

       \(\frac{x}{5}\)     \(=\frac{42}{55}\)   

\(\frac{x\cdot11}{55}\)   \(=\frac{42}{55}\)

    \(\Rightarrow x\cdot11=42\)

         \(x\)     \(=42:11\)

         \(x\)    \(=\frac{42}{11}\)