Remember you cannot take the log of a negative value or of zero. So that means the argument must be greater than zero (i.e. the argument must be positive)
Set the inner expression greater than zero
Subtract 4 from both sides
Combine like terms on the right side
So that means t must be greater than -4
So here is the domain in interval notation: (-4,)
Notice if we graph (just replace t with x), we get
notice how the graph never crosses the line . So this graphically verifies our answer.