Question

how do i do this ? and show it step by step please

Answer 1

$\dfrac{2}{a}-\dfrac{6}{a}=\dfrac{2-6}{a}=\boxed{\frac{-4}{a}=-\frac{4}{a}}\\\\\\-\dfrac{7}{10}-\left(-\dfrac{6}{10}\right)=\dfrac{-7}{10}+\dfrac{6}{10}=\dfrac{-7+6}{10}=\boxed{\frac{-1}{10}=-\frac{1}{10} }$