What happens when a positive and a negative multiply?
What happens when a positive and a negative multiply?
When you multiply a negative number by a positive number then the product is always negative. When you multiply two negative numbers or two positive numbers then the product is always positive. Now we have two negative numbers, so the result is positive.
How does multiplying negative and positive numbers work?
Using the fact multiplication is commutative, a negative times a positive is also negative. Similarly, we can prove that a negative times a negative is a positive. Since we know that −ab is negative, and the sum of these two terms is 0, therefore (−a) × (−b) is positive.
What is the rule for positive and negative numbers?
The rules for multiplication and division are simple: If both numbers are positive, the result is positive. If both numbers are negative, the result is positive. (Basically, the two negative values cancel each other out).
What happens when you multiply a positive number by a number greater than 1?
Whenever you multiply a positive number by a factor greater than 1, the product will be larger than the original number. Whenever you multiply a positive number by a positive factor less than 1, the product will be smaller than the original number.
Why when you multiply a negative by a negative it is positive?
Each number has an “additive inverse” associated to it (a sort of “opposite” number), which when added to the original number gives zero. The fact that the product of two negatives is a positive is therefore related to the fact that the inverse of the inverse of a positive number is that positive number back again.
How do you do positives and negatives in math?
Once you have the numerical answer, then you can apply a very simple rule to determine the sign of the answer:
- When the signs of the two numbers are the same, the answer will be positive.
- When the signs of the two numbers are different, the answer will be negative.
Why minus multiply minus is plus?
This is in fact the reason why the negative numbers were introduced: so that each positive number would have an additive inverse. The fact that the product of two negatives is a positive is therefore related to the fact that the inverse of the inverse of a positive number is that positive number back again.
What’s a negative times a positive?
Rule 2: A negative number times a positive number equals a negative number. When you multiply a negative number to a positive number, your answer is a negative number. It doesn’t matter which order the positive and negative numbers are in that you are multiplying, the answer is always a negative number.
Do two negatives make a positive when adding?
When you have two negative signs, one turns over, and they add together to make a positive. If you have a positive and a negative, there is one dash left over, and the answer is negative.
Does multiplying 2 negatives equal a positive?
The fact that the product of two negatives is a positive is therefore related to the fact that the inverse of the inverse of a positive number is that positive number back again. Even in such general, non-numerical contexts, the property that the product of two negative things is positive still holds.
What are the rules for multiplying positive and negative numbers?
You also have to pay attention to the signs when you multiply and divide. There are two simple rules to remember: When you multiply a negative number by a positive number then the product is always negative. When you multiply two negative numbers or two positive numbers then the product is always positive.
How do you multiply positive numbers with negative numbers?
Multiply a positive number by a negative number. To do this, multiply the integers as usual, then add a negative sign to the product. A positive number multiplied by a negative number is always negative.
What are the rules for adding positive and negative numbers?
Adding Positive and Negative Numbers Rule 1: Adding positive numbers to positive numbers—it’s just normal addition. Rule 2: Adding positive numbers to negative numbers—count forward the amount you’re adding. Rule 3: Adding negative numbers to positive numbers—count backwards, as if you were subtracting.
Why multiplying negatives equal a positive?
To sum up, the reason that multiplying two negative numbers makes a positive number is that you’re going backwards, backwards.
