for the first one:
[tex]t \: - \: 2e = 20[/tex]
you change the subtract 2 to add 2 on both sides. so it looks like the picture above. Then you would add 20 + 2 to equal 22. Then you divide that by 1 (from the t). that equals 22, so thats the answer.
[tex]t = 22[/tex]
