# Adding Integers

Integers are added in the same fashion as whole numbers, except that certain rules should be applied.

If you **add integers with different signs**, i.e. one is positive and another is negative, then subtract negative number without minus from positive number.

Note, that if **you add negative number and positive**, you'are actually subtract negative integer without minus from positive integer, that is `color(blue)(a+(-b)=a-b)`.

**Example 1**. Find `46+(-21)`.

We actually want to subtract 21 from 46: `46-21=35`.

So,** `46+(-21)=35` **.

Next example.

**Example 2**. Find `-35+21`.

We actually want to subtract 35 from 21: `21-35=-14`.

If you're not comfortable with subtracting bigger number from smaller then change sign of each number: now we want to find 35-21=14.

And change sign back: 14 transforms into -14.

So,** `-35+21=-14` **.

- If you
**add two positive numbers**, you're actually adding whole numbers. - If you
**add two negative numbers**, add numbers without minus and then place minus in front of result, i.e. `color(green)(-a-b=-(a+b))`.

**Example 3**. Find `23+51`.

`23+51=74`.

Another example.

**Example 4**. Find `-48+(-19)`.

Ignore minuses: `48+19=67`. Place minus in front of result: -67.

So,** `-48+(-19)=67` **.

Final example shows how to add more than two integers.

**Example 5**. Find `-48+(-45)+34`.

We do such problems step-by-step.

First find `-48+(-45)`. Ignore minuses: `48+45=93`. Set minus in front of result: -93.

Now we are left with `-93+34`. Change sign of every number: `93-34=59`.

Change sign back: -59.

So,** `-48+(-45)+34=-59` **.

Now, it's your turn. Take pen and paper and solve following problems.

**Exercise 1**. Find 36+(-21).

**Answer**: 15.

**Exercise 2**. Find -57+60.

**Answer**: 3.

**Exercise 3**. Find -100+69.

**Answer**: -31.

**Exercise 4**. Find -45+(-60).

**Answer**: -105.

**Exercise 5**. Find -65+(-34)+(-35)+21+(-45)+100.

**Answer**: -58.