\(-1-\left(\dfrac{13}{23}+\dfrac{2}{7}\right)-\dfrac{10}{23}+\dfrac{9}{7}\)
\(=-1-\dfrac{13}{23}-\dfrac{2}{7}-\dfrac{10}{23}+\dfrac{9}{7}\)
\(=\left(-\dfrac{13}{23}-\dfrac{10}{23}\right)+\left(-1\right)+\left(\dfrac{9}{7}-\dfrac{2}{7}\right)\)
\(=\dfrac{-23}{23}+\left(-1\right)+\dfrac{7}{7}\)
\(=\left(-1\right)+\left(-1\right)+1\)
\(=-1\)
\(=-1-\dfrac{13}{23}-\dfrac{2}{7}-\dfrac{10}{23}+\dfrac{9}{7}=-1-\left(\dfrac{13}{23}+\dfrac{10}{23}\right)-\left(\dfrac{2}{7}-\dfrac{9}{7}\right)=-1-1-\left(-1\right)=-1\)
`-1 -( 13/13 + 2/7 ) - 10/23 + 9/7`
`=-1 - 13/23 - 2/7 - 10/23 +9/7`
`=-1 -( 13/23 + 10/23) + (9/7 - 2/7)`
`= -1 -1 +1`
`=-1`
