HOW TO multiply negatives
King Education :: Ask Questions :: Math
Page 1 of 1
HOW TO multiply negatives
The rule of how to multiply negatives is simple:
To multiply a negative number by any number, take the (positive) opposite of the negative number and multiply it by the other number, and take the opposite of that
Negative by positive number
For a case where a negative number is multiplied by a positive, the rule above can be restated as: take the positive number, and the negative WITHOUT the minus sign, multiply them and add the inus sign to the product.
Example: multiply 5 and -3.
Take 5 and -3 without the "-" sign: 5 and 3
Multiply them: 5*3 = 15.
Add the minus sign: -15.
Conclusion: Product of a negative and a positive is always a negative number.
Negative by negative number
When you have to multiply two negative numbers, such as (-5) * (-3), the rule above should be applied twice:
(-5)*(-3) is the opposite of 5*(-3), which is the opposite of the opposite of 5*3.
5*3 is 15
Opposite of 15 s -15.
Opposite of opposite of 15 is opposite of -15, and opposite of -15 is 15 again.
Conclusion: Product of a negative multiplied by negative is always POSITIVE.
Here's a handy table: sign of result when we multiply
Multiply: Positive Negative
Positive + -
Negative - +
Examples:
2*3=6
2*(-3) = -6
(-2)*3 = -6
(-2)*(-3) = 6
To multiply a negative number by any number, take the (positive) opposite of the negative number and multiply it by the other number, and take the opposite of that
Negative by positive number
For a case where a negative number is multiplied by a positive, the rule above can be restated as: take the positive number, and the negative WITHOUT the minus sign, multiply them and add the inus sign to the product.
Example: multiply 5 and -3.
Take 5 and -3 without the "-" sign: 5 and 3
Multiply them: 5*3 = 15.
Add the minus sign: -15.
Conclusion: Product of a negative and a positive is always a negative number.
Negative by negative number
When you have to multiply two negative numbers, such as (-5) * (-3), the rule above should be applied twice:
(-5)*(-3) is the opposite of 5*(-3), which is the opposite of the opposite of 5*3.
5*3 is 15
Opposite of 15 s -15.
Opposite of opposite of 15 is opposite of -15, and opposite of -15 is 15 again.
Conclusion: Product of a negative multiplied by negative is always POSITIVE.
Here's a handy table: sign of result when we multiply
Multiply: Positive Negative
Positive + -
Negative - +
Examples:
2*3=6
2*(-3) = -6
(-2)*3 = -6
(-2)*(-3) = 6
King Education :: Ask Questions :: Math
Page 1 of 1
Permissions in this forum:
You cannot reply to topics in this forum
|
|
Fri Mar 27, 2015 3:13 pm by Admin
» Units conversion examples
Fri Mar 27, 2015 3:03 pm by Admin
» HOW TO multiply negatives
Fri Mar 27, 2015 3:02 pm by Admin
» Join King Education
Thu Mar 26, 2015 1:00 pm by Admin
» Your first subject
Thu Mar 26, 2015 11:28 am by Admin