50= - 10t+80
We move all terms to the left:
50 - ( -10t+80) =0
Get rid of the parentheses
10t - 80+50=0
We add all the numbers together, and all the variables
10+ - 30=0
We move all the terms containing t to the left, all the other terms to the right
10t = 30
t = 30/10
t = 3
