Answer:
$-118
Step-by-step explanation:
She owes the bank $64. She then paid the bank $25 because she owes $64. She has only paid $25 out of the $64 that she owes so you would subtract 25 from 64 and you would get 39. This means that she STILL owes the bank $39. She then charges, or uses, $79 which brought the amount she owes back up. So she used to owe $64 but then she paid $25 of the $64. She has $39 left to pay, but then she used $79 so you would add 79 and 39 because those are the two amounts of money that she owes. Integer wise, the numbers 79 and 39 would become -39 and -79. -79 and -39 added together is $-118. So now the balance, or amount she owes, is $-118. I hope this made sense.
