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PLS HELP!!!Arlene is showing her work in simplifying āˆ’7.9 + 8.2 āˆ’ 3.4 + 2.1. Identify any errors in her work or in her reasoning. Write feedback to Arlene explaining the mistake she made and how to correct her work.
the way she did it was

Step Work Reasoning
āˆ’7.9 + 8.2 āˆ’ 3.4 + 2.1 Original problem
1 āˆ’7.9 + 8.2 + (āˆ’3.4) + 2.1 Additive inverse
2 āˆ’7.9 + (āˆ’3.4) + 8.2 + 2.1 Associative property
3 (āˆ’7.9 + (āˆ’3.4)) + (8.2 + 2.1) Commutative property
4 āˆ’11.3 + 10.3 Simplify
5 āˆ’1 Simplify

Respuesta :

I started with -7.9+8.2-3.4+2.1=-1.
botellok

Answer:

The errors are in 2 and 3 step.

Step-by-step explanation:

The first step is correct.

Now, in the second step she rearranged positive terms on right and negative terms on left, that is posible by commuttative property, not associative.

Then, she grouped each pair of terms, that is posible by associative property, not commutative.

4 and 5 step are correct.

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