Question

3. Emma said that when you multiply three negative decimals , the product will be positive . Use these numbers to answer the questions: -2.5,-3.8,-2.; .7, - 4.5

Part A: Is Emma's statement always true, sometimes true, or always false? Write two equations to support your answer.

Part B: Write a rule for multiplying three negative decimals .

Part C Emma changed her statement to say that when you multiply two negative decimals and a positive decimal the product will be positive Emma's new statement always true , sometimes true or always false ? Write two equations to support your answer

Answer 1

Using multiplication signal rules, it is found that:

A: Emma's statement is always false.

B: The result is always negative.

C: Emma's statement is always true.

The rule used for this exercise is as follows:

• When two numbers of different signals are multiplied, the result is negative.
• When two numbers have the same signal, the result is positive.

Part A:

• Three numbers are multiplied, all negative.
• The multiplication of the first two result in a positive number.
• Then, this positive number is multiplied by a negative number, and the result will be negative, which mean that Emma's statement is always false.

Two examples are:

$-2.5(-3.8)(-2) = 9.5(-2) = -19$

$-2.5(-2)(-0.7) = 5(-0.7) = -3.5$

Part B:

The rule is that the result is always negative.

Part C:

• The multiplication of the first two negative numbers result in a positive number.
• Then, this positive number is multiplied by another positive number, and the result will be positive, which mean that Emma's statement is always true.

Two examples are:

$-2.5(-3.8)(2) = 9.5(2) = 19$

$-2.5(-2)(0.7) = 5(0.7) = 3.5$

A similar problem is given at https://brainly.com/question/24764960