Simply take away another 1. -4 - 1 = -5.
9
4
(-5) + (-4) = -9
4
Negative 5 is less than negative 4.
It is: -4+5 = 1
9
-9 + 4 = -5 (negative 5)
A negative times a negative is a positive (-4)(-5) = positive 20
4 - (-5) = 4 + 5 = 9.
5
The two negatives cancel out so a negative over a negative is positive. So, -4/-5 = 4/5 or 0.8