Answer :

1) 13.02-6y=8y
          +6y=6y
        13.02=14y    then divide both sides by 14. you get y= .93
2) 1/5x+5=19-1/2x
           -5=-5
    (1/5x=14-1/2x)5
     x=70-2.5x
   +2.5x=+2.5x
    3.5x=70 divide both sides by 3.5 and you get x=20
3) 7.3t+22=2.1t-22.2
  -2.1t      =-2.1t
    5.2t+22=22.2
          -22=-22
         5.2t=-44.2 divide both by 5.2 and t=-8.5
4) (1.4+2/5e=3/15e-.8)15
    21+6e=3e-12
        -3e=-3e
    21+3e=-12
   -21     =-21
         3e=-33 divide both by 3 and e=-11
5) 5(x-4)=2(2x+5)
    5x-20=4x+10
    -4x     -4x
     x-20=10
      +20=+20
          x=30
6) -7(3+t)=4(2t+6)
     -21-7t=8t+24
         +7t=+7t
    -21=15t+24
    -24=     -24
    -45=15t divide both by 15 and t=-3
7) (3/4x+6=1/3x+9)4
    3x+24=1.3x+36
   -1.3x   =-1.3x
   1.7x+24=36
         -24=-24
   1.7x    =12 divide both sides by 1.7 and x=7.06