Ch. 1.4 | Operations with Integers

Question 1

Absolute Value

Answer 1

|x| = {-x if x ≤ 0} {x if x ≥ 0}

The first is read as: “the absolute value of x is equal to the opposite (additive inverse) of x if x is negative.”

The second is read as: “the absolute value of x is equal to x if x is positive or zero.”

The number of units between an integer and zero.

Question 2

Integers

Answer 2

The set of integers is made up of positive integers, negative integers, and zero.

{…, -3, -2, -1, 0, 1, 2, 3, …}
Zero separates the positive integers from the negative integers.

Question 3

Opposite Value

Answer 3

Two numbers (a) and (-a), such that a + (-a) = 0

or additive integers

Question 4

Subtraction

Answer 4

Adding the opposite, (a) - (b) = (a) + (-b).