Question

What is the value of the following expression?

Answer 1

The expression (−81)(−9)  will give the value of 729.

Step-by-step explanation:

The given expression is (−81)(−9) .

The both numbers in the expression are negative numbers and they are given inside the brackets.

This means that, the negative numbers must be multiplied to get a final value.

The rules in multiplication are :

• Positive number × Positive number = positive number
• Negative number × Positive number = negative number
• Positive number × Negative number = negative number
• Negative number × Negative number = positive number

From the rules, it can be determined that the result of any two negative numbers will be a positive number.

So, eliminate option A) and B) because they have negative sign.

The expression (−81)(−9) = -81 × -9

⇒ 729.

Therefore, the option C) and D) are not in match with 729. None of the options are not the value of the given expression (−81)(−9).