1986 AIME Problem 4

Determine 3 x_{4}+2 x_{5} if x_{1}, x_{2}, x_{3}, x_{4} and x_{5} satisfy the system of equations given below:

\begin{aligned} 2 x_{1}+x_{2}+x_{3}+x_{4}+x_{5}= & 6 \\ x_{1}+2 x_{2}+x_{3}+x_{4}+x_{5}= & 12 \\ x_{1}+x_{2}+2 x_{3}+x_{4}+x_{5}= & 24 \\ x_{1}+x_{2}+x_{3}+2 x_{4}+x_{5}= & 48 \\ x_{1}+x_{2}+x_{3}+x_{4}+2 x_{5}= & 96 \end{aligned}