math challenge/riddle question?

[PadfootPatronus]

'The following puzzle requires you to sub one digit for A, and one digit for B. (This is not algebra). the digits are between 1 and 9. Neither A nor B will be zero.

AA x BA / A -15 = BAB

i need to know what BAB is. this is not homework, so please just answer thanks
yes i think BAB will be negative

 

[sool1]

Wait, I'm confused. If the digits are between 1 and 9, and A is <15, wouldn't BAB be a negative number?