Note. When many like quantities are to he added together ^ 

 ^whereof some are affirmative and others negative ; reduce 

 them first to two terms, by adding all the affirmative quan- 

 tities together, and all the negative ones j and then add 

 the two terms according to the rule. Thus, 



11. Add 4^ *-|-7ri*— 3^*4-12^'' — Srt'+^*.— 5^* to- 

 gether. 



First, 4o*-j-7a**{-i2fl*-|-a*zr24^?% the sum of the af- 

 firmative quantities. 



And — 3a* — 8a* — 50*= — i6a^y the sum of the nega- 

 tive. 



Then 24^*^1 6a* =8/3% the sum of the whole. 



12. Add 5a»*— "4aAf*-|-i0fl;c* — 8fl;v*-— j5a;r* together. 

 First, ^ax *-|- 1 oax * = i ^ax^y 



And — 4fl/)f ^ — ^ax"- — ^ax"" = — l ^ax^ j 



Therefore the sum of these quantities is -{-15^;^*— -i8a 



^3- 14- , 



— 6^ ax — 2y '\-2ax^ 



+ 2\/aX + y + ^«* 



-— 6^ ax ""^Jy — 3^^* 



+ iov/'«;v +Sy +3^^* 



Li case 



