[tex]n+7=8[/tex]
Subtract the 7 from 8, which would then get you...
[tex]n=1[/tex]
Isolate the n. Note the equal sign. What you do to one side, you do to the other.
Subtract 7 from both sides
n + 7 (-7) = 8 (-7)
n = 8 - 7
n = 1
1 is your answer
hope this helps