x+12=50
7/9 / 2
1.8*10^-2/0.0831*500
-5x=45
35 x 2/5
9/28 x 7/27
6 1/5 as an improper fraction in simplest form
-a^3-a^2+3a-1=0
8/7 / 2/35
-6x+1=7x-12
