Answer
The system can not be solved by using Cramer's Rule because the determinant of the coefficient matrix equals to zero.
Work Step by Step
The coefficient matrix is
$A=\left[\begin{array}{cc}
-0.4&0.8\\
2&-4
\end{array}\right]$
such that $AX=B$
and
$X=\left[\begin{array}{cc}
x_1\\
x_2
\end{array}\right]$ and $B=\left[\begin{array}{cc}
1.6\\
5
\end{array}\right]$
$|A|=4*0.4-2*0.8=1.6-1.6=zero$
Thus, the system can not be solved by using Cramer's Rule.