Solve:

y2yy+2y=30e4t\displaystyle {y}{'''}-{2}{y}{''}-{y}'+{2}{y}=-{30}{e}^{{{4}{t}}}

y(0)=4,y(0)=10,y(0)=28\displaystyle {y}{\left({0}\right)}=-{4},\quad{y}'{\left({0}\right)}=-{10},\quad{y}{''}{\left({0}\right)}=-{28}

y(t)\displaystyle {y}{\left({t}\right)} =