Step-by-step explanation:
[tex]\bold{PART\ A}\\\\-np-80<60\qquad\text{add 80 to both sides}\\\\-np-80+80<60+80\\\\-np<140\qquad\text{change the signs}\\\\np>-140\\\Downarrow\\\text{if}\ p>0,\ \text{then}\ \boxed{n>-\dfrac{140}{p}}\\\\\text{if}\ p<0,\ \text{then}\ \boxed{n<-\dfrac{140}{p}}[/tex]
[tex]\bold{PART\ 2}\\\\2a-5d=30\qquad\text{subtract}\ 2a\ \text{from both sides}\\\\2a-2a-5d=30-2a\\\\-5d=30-2a\qquad\text{divide both sides by (-5)}\\\\\dfrac{-5d}{-5}=\dfrac{30-2a}{-5}\\\\\boxed{d=\dfrac{2a-30}{5}}[/tex]
