# Calculating steady state output using Laplace transform

I've tried to obtain the the steady state output with the help of final value theorem and multiplication properties of Laplace transform.But I'm not sure whether I've solved the problem correctly or not. Please let me know if any corrections are required.

This is the question.

This is the approach I've tried. The solution is 45. But I'm not sure whether I've made the correct assumption of input signal x(t) as a step signal with amplitude 5.