



 
Hi Natasha, To solve for $a$ in this problem \[\frac{9a}{9} > 81\] you can cancel the $9$ in the numerator with the $9$ in the denominator to get $a > 81.$ You need to change the direction of the inequality if you multiply each side of the inequality by a negative number. Thus, for example, if your question had been to solve $9 a > 81$ then I would multiply each side by $\frac{1}{9}$ and the inequality becomes \[\frac{1}{9} \times (9 a) < \frac{1}{9} \times 81\] or \[a < 9.\] I hope this helps,  


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