I agree with Justin for the first part because if you multiply a positive integer by a negative integer it would me a negative integer.
But for the second part I don't agree because it would be positive if you remove 5 by a negative number.
a) (+2) x (+4) = +8
b) (+3) x (-5) = -15
(If the integer signs are the same the product is positive, if the integer signs are different/opposite the product is negative)
a) (+10) x (+4) = +40
b) (+6) x (-5) = -30
c) (-7) x (+5) = -35
d) (-8) x (-4) = +32
I couldn't find a link, so
Here is the Multiplying Integers song :)