Use LaTeX:  \displaystyle a_1=5 and LaTeX:  \displaystyle a_2=-8 and LaTeX:  \displaystyle a_n=3a_{n-1} +7a_{n-2} to find LaTeX:  \displaystyle a_{6}

Finding the next term in the sequence gives LaTeX:  \displaystyle a_3=(3)(5)+(7)(-8)=-41
LaTeX:  \displaystyle a_{4}=(3)(-8)+(7)(-41)=-311 .
LaTeX:  \displaystyle a_{5}=(3)(-41)+(7)(-311)=-2300 .
LaTeX:  \displaystyle a_{6}=(3)(-311)+(7)(-2300)=-17033 .