false,,,,,, becoz u r using biconditional (iff)
we know any row/column is constant multiple of any other row/column ⇒ matrix is singular ,,,,is true
but other way
A matrix is singular ⇒ any row/column is constant multiple of any other row/column ,,,,,,,,not neccesry condition
for example
|A| = 0(1-0) - 1(-1-0) + 1(0-1)
= 0
here matrix is singular but not any row/column is constant multiple of any other row/column.
so any row/column is constant multiple of any other row/column ⇒ matrix is singular (only one way true)