can someone break down how to take the integral of this problem?

Question

20te^-10t dt

Answer 1

e^-10t dt -10te^-10t dt= te^-10t
e^-10tdt=(e^-10t)/-10
10te^-10tdt=(e^-10t)/(-10)-te^-10t
20te^-10t dt =(e^-10t)/(-5)-2te^-10t