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Here are some tips for Integer Multiplication, which aligns with Florida state standards:

**Integer Multiplication**

To review the Fast Multiplication topic, see here.

FACT |

1 × ^{-}1 = ^{-}1 and ^{-}1 × ^{-}1 = 1 |

Breakdown of how integer multiplication works

Steps for integer multiplication:

^{-}4 × 7= (4 × ^{-}1) × 7^{-}3 ×^{-}5= (3 × ^{-}1) × (^{-}1 × 5)= ^{-}1 × (4 × 7)= ( ^{-}1 ×^{-}1) × (3 × 5)= ^{-}1 × 28= 1 × 15 = ^{-}28= 15

- Count the number of negative integers
- Ignore the negative signs and multiply as usual
- If needed, add a negative sign to the answer in Step 2

Odd number of negative integers = negative product

Even number of negative integers = positive product

**Example 1: ** ^{-}2 × ^{-}3 × ^{-}7

Step 1: Count the negatives

There are 3 negative integers in the equation.

Step 2: Multiply

2 × 3 × 7 = 42

Step 3: Add negative sign?

Since there are 3 negative integers, the product must be negative.

^{-}2 ×^{-}3 ×^{-}7 =^{-}42

**Example 2: ** ^{-}1 × 4 × ^{-}3 × 4

Step 1: Count the negatives

There are 2 negative integers in the equation.

Step 2: Multiply

1 × 4 × 3 × 4 = 48

Step 3: Add negative sign?

Since there are 2 negative integers, the product must be positive.

^{-}1 × 4 ×^{-}3 × 4 = 48

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