[tex]-np-80 < 60\qquad\text{change the signs}\\\\np+80<-60\qquad\text{subtract 80 from both sides}\\\\np<-140\qquad\text{divide both sides by}\ p\neq0\\\\if\ p>0,\ then\ n<-\dfrac{140}{p}\\\\if\ p <0\ then\ n>-\dfrac{140}{p}[/tex]
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[tex]2a-5d=30\qquad\text{subtract 2a from both sides}\\\\-5d=-2a+30\qquad\text{change the signs}\\\\5d=2a-30\qquad\text{divide both sides by 5}\\\\d=0.4a-6[/tex]
