<PRE><B>Question 594465</B>
13 is a prime number - no factors except 1 and 13


one of the factors of -135, plus the other factor of 135 multiplied by 13; have to sum to -56


factors for -135 (one of the pair must be negative) ___ (1,135), (3,45), (5,27), (9,15)


none of the pairs of possible factors work, so the expression is not factorable
___ you can confirm this by using the quadratic formula</PRE>