Answer :
[tex](3a+6):3+18=50 \\\\ (3a+6):3=50-18 \\\\ (3a+6):3=32 \\\\ 3a+6=32*3 \\\\ 3a+6=96 \\\\ 3a=96-6 \\\\ 3a=90 \\\\ a=90:3 \\\\ \boxed{a=30} [/tex]
if 3xa=3 times a then
so the quantity (3xa+6) is divided by 3 so factor out the three and get 3(a+2) divide by three and get (a+2)+18 and the associative property of addition allows us to move the parenthasees to (a+2+18)=50 or a+20=50 subtract 20 from both sides and get
a=30
or (3a+6)/3+18=50
3(a+2)/3+18=50
a+2+18=50
a+20=50
a=30
