[tex]zad.f\\\\-(x^{2} +x+1)-(-x^{2} +x-1)+(-x^{2} -x-1)=-x^{2} -x-1+x^{2} -x+1-x^{2} -x-1=-x^{2} -3x-1\\\\zad.g\\\\(\dfrac{1}{2} x+y-\dfrac{1}{6} )\cdot (-12)=\dfrac{1}{2} x\cdot (-12)+y\cdot (-12)-\dfrac{1}{6}\cdot (-12)=-6x-12y+2\\\\zad.h\\\\(35k-28m+70)\div 7 =(35k-28m+70)\cdot \dfrac{1}{7} =35k \cdot \dfrac{1}{7} -28m \cdot \dfrac{1}{7}+70\cdot \dfrac{1}{7}=5k-4m+10[/tex]