-(72) = -49
Natural numbers = {1,2,3,4,...}
Whole numbers = {0,1,2,3,4,...}
0 is the only whole number that isn't a natural number.
Integers {...,-3,-2,-1,0,1,2,3,...}
Rational numbers are number that can be written as fractions
with an integer in the numerator and the denominator. So
integers are rational numbers because they can have a 1
denominator place underneath them.
Edwin