=-85/23-2/7-7/23+9/7
=(-2/7+9/7)+(-85/23-7/23)
=1+(-92/23=-4)
=-3
=
\(-3-\dfrac{16}{23}-\dfrac{2}{7}-\dfrac{7}{23}+\dfrac{9}{7}\)
\(=-3-\left(\dfrac{16}{23}+\dfrac{7}{23}\right)-\left(\dfrac{2}{7}-\dfrac{9}{7}\right)\)
\(=-3-\dfrac{23}{23}-\dfrac{-7}{7}\)
\(=-3-1-\left(-1\right)\)
\(=-3-1+1\)
\(=-3\)