Again, Jjmarie, please do not ask questions about equations in this format. Your job is to SOLVE 3(13-2a)=-3+a, not to find out "what it equals."
"Solve" means "find the value of a that satisfies the given equation."
3(13-2a)=-3+a, when multiplied out, is 39 - 6a = -3 + a
Combining like terms: -7a = -42, or a = 6. See? a equals 6; the equation does not equal 6. You could say, however, that "3(13-2a)=-3+a" is TRUE when a = 6. It's a conditional statement.