Question

3 phan x-5 =21 phan 105

tìm x 

giúp tôi

Answer 1

\(\frac{3}{x-5}=\frac{21}{105}\)

\(\Rightarrow x-5=3:\frac{21}{105}\)

\(\Rightarrow x=15+5\)

\(\Rightarrow x=20\)

Answer 2

\(\frac{3}{x}-5=\frac{21}{105}\)

\(\Rightarrow\frac{3}{x}=\frac{26}{5}\)

\(\Rightarrow26x=15\Rightarrow x=\frac{15}{26}\)

Answer 3

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