Answer :
[tex]3t-7=5t\\\\3t-5t=7\\\\-2t=7\\\\To\ obtain\ 6t\ on\ left\ side\ we\ multiply\ by\ -3\ both \ sides\\\\\-2t*(-3)=-3*7\\\\Solution:\ 6t=-21[/tex]
[tex]3t-7=5t\ \ \ \ |add\ 7\ to\ both\ sides\\\\3t=5t+7\ \ \ \ \ \ |subtract\ 5t\ from\ both\ sides\\\\-2t=7\ \ \ \ \ |divide\ both\ sides\ by\ (-2)\\\\t=-3.5\\\\6t=6\times(-3.5)=-21[/tex]