\(\dfrac{y-1}{12y}+\dfrac{2y+7}{12y}+\dfrac{6-3y}{12y}=\dfrac{y-1+2y+7+6-3y}{12y}=\dfrac{12}{12y}=\dfrac{1}{y}\)
\(\dfrac{3x+8}{x+7}-\dfrac{x-6}{x+7}=\dfrac{3x+8-\left(x-6\right)}{x+7}=\dfrac{3x+8-x+6}{x+7}=\dfrac{2x+14}{x+7}=\dfrac{2\left(x+7\right)}{x+7}=2\)