A couple points:

When using DBI and prepare, use placeholders. If you don't know what they are, read the doc. To put it simply, you can put a ? in the prepare statement, pass values for each in the execute, and it will properly quote it for you. In your case, something like this 

my $dbh = $db->prepare("SELECT balance FROM Table1 WHERE username=? an
+d balance < '-.01'");
$dbh->execute($authuser);
my ($balance_due) = $dbh->fetchrow_array;

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would work. This is good for untrusted data.

Anyway, the easiest solution to your problem would be to simply negate the value, which would yield a positive. So something like 

$balance_due = -$balance_due

# or

$balance_due = $balance_due * -1;

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would be good and result in $balance_due being equal to 9.99.

To answer your question using a different way, you could also use a substitution regex 

$balance_due =~ s/-//;

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to strip out (literally replace it with nothing) the first - it finds. If you don't understand what it going on, read up on perlretut.

Added Second paragraph.

In reply to Re: Chomp Maybe? by The Mad Hatter
in thread Chomp Maybe? by th3monk3y

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