Adding and subtracting integers

Adding and subtracting positive and negative integers using the number line and the rules for adding or subtracting a negative.

Adding or subtracting a positive

Adding a positive number moves right on the number line. Subtracting a positive number moves left.

$-3 + 5 = 2$ and $-3 - 5 = -8$.

Integer calculator

Move the sliders and watch the rules. Notice that a − (negative) gives a bigger answer than a.

Example 1●

Find (a) $-6 + (-4)$ and (b) $-6 - (-4)$.

(a) $-6 - 4 = -10$

(b) $-6 + 4 = -2$

Example 2●●

A bank balance is $-\$45$. A deposit of $\$120$ is made and then a fee of $\$12$ is charged. Find the balance.

$-45 + 120 - 12 = 75 - 12 = 63$

The balance is $\$63$.

Flashcards

$a + (-b)$

$a - b$

$a - (-b)$

$a + b$

$-8 - 3$

$-11$

Practice

Find $-3 + 5$.
Find $-3 - 5$.
Find $7 + (-10)$.
Find $7 - (-10)$.
Find $-6 + (-4)$.
Find $-6 - (-4)$.
A balance of $-\$45$ has $\$120$ deposited and a $\$12$ fee taken out. Find the balance in dollars.
The temperature rises from $-8^\circ$C to $7^\circ$C. By how many degrees did it rise?