Question

×/7-×=1/21

Help me

Answer 1

\(\dfrac{x}{7}-x=\dfrac{1}{21}\)

=> \(\dfrac{x-7x}{7}=\dfrac{1}{21}\)

=> \(\dfrac{-6x}{7}=\dfrac{1}{21}\)

=> -6x.21=7

=> -126.x=7

=> x=\(\dfrac{7}{-126}=\dfrac{-1}{18}\)

Answer 2

\(\dfrac{x}{7}-x=\dfrac{1}{21}\Leftrightarrow\left(\dfrac{1}{7}-1\right)x=\dfrac{1}{21}\Leftrightarrow\dfrac{-6}{7}x=\dfrac{1}{21}\)

\(x=\dfrac{-6.21}{7}=-6.3=-18\)

Answer 3

\(\dfrac{x}{7}-x=\dfrac{1}{21}\Leftrightarrow\left(\dfrac{1}{7}-1\right)x=\dfrac{1}{21}\Leftrightarrow x=\dfrac{\dfrac{1}{21}}{\dfrac{-6}{7}}=\dfrac{1}{21}.\left(-\dfrac{7}{6}\right)=-\dfrac{1}{18}\)