The given system of equations is,
x+y+z=1 2x+3y+2z=2 ax+ay+2az=4
Write the system of equations in the form of AX=B.
[ 1 1 1 2 3 2 a a 2a ][ x y z ]=[ 1 2 4 ]
Now, the determinant of A is,
| A |=1( 3×2a−a×2 )−1( 2×2a−a×2 )+1( 2×a−a×3 ) =4a−2a−a =a
Since, | A |≠0. Therefore, inverse of matrix A exists.
Hence, the system of equations is consistent.