Question 1129196
.
It does exist.


Every 2x2-matrix has the determinant.    (So you could do not add that  "if . . . "  statement in your post)


To learn on how to calculate it  (it is as easy as 2x2),  read the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Matrices-and-determiminant/What-is-a-matrix.lesson>What is a matrix?</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Matrices-and-determiminant/Determinant-of-a-2x2-matrix.lesson>Determinant of a 2x2-matrix</A> 

in this site.


After learning it, &nbsp;you will be in &nbsp;MUCH &nbsp;BETTER &nbsp;POSITION, &nbsp;and will be able to do such simple things on your own, 
without asking for assistance from outside.