Given:
A homogeneous system of linear equations Ax= 0 is given.
If the determinant of A is 0 then Ax = 0 has infinitely many solutions.
If the determinant is zero that means the matrix A is not invertible.
That implies there exists a non zero x such that Ax=0 that is,
Then by linearity of A, every scalar multiple of x is mapped to zero by A.
Therefore, the system yields an infinite number of solutions.
Therefore, the statement is a true statement.