a: \(-\dfrac{36}{24}=\dfrac{-36:12}{24:12}=\dfrac{-3}{2}\)
\(\dfrac{3^2\cdot2^5}{18}=\dfrac{9\cdot32}{9\cdot2}=\dfrac{32}{2}=16\)
\(\dfrac{8\cdot15-3\cdot15}{30-45}=\dfrac{-15\cdot5}{15}=-5\)
b: -17/12=-255/180
31/18=(31*10)/(18*10)=310/180
-8/15=(-8*12)/(15*12)=-96/180