Question

Tìm x, biết:

a) \(\frac{x-1}{x-5}=\frac{6}{7}\left(x\ne5\right)\)

b)\(\frac{x^2}{6}=\frac{24}{25}\)

Answer 1

a.

\(\frac{x-1}{x-5}=\frac{6}{7}\)

\(\left(x-1\right)\times7=6\times\left(x-5\right)\)

\(7x-7=6x-30\)

\(7x-6x=-30+7\)

\(x=-23\)

b.

\(\frac{x^2}{6}=\frac{24}{25}\)

\(x^2=\frac{24}{25}\times6\)

\(x^2=\frac{144}{25}\)

\(x^2=\left(\pm\frac{12}{5}\right)^2\)

\(x=\pm\frac{12}{5}\)

Vậy \(x=\frac{12}{5}\) hoặc \(x=-\frac{12}{5}\)

 

Answer 2

CÓ VẤN ĐỀ ._.

Answer 3

b) \(\frac{x^2}{6}=\frac{24}{25}\)

\(\Rightarrow x.25=24.6\)

\(\Rightarrow x.25=144\)

\(\Rightarrow x=\frac{144}{25}\)

\(\Rightarrow x=5,76\)

Vậy x = 5,76

Answer 4

a) Ta có :

\(\frac{x-1}{x-5}=\frac{6}{7}\)

\(\Rightarrow7.\left(x-1\right)=6\left(x-5\right)\)

\(\Rightarrow7x-7=6x-30\)

\(\Rightarrow7x-6x=-30+7\)

\(\Rightarrow x=-23\)

Vậy \(x=-23\)

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