Question

Arlene is showing her work in simplifying −7.9 + 8.2 − 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.

Answer 1

what did she solve

Answer 2

i only see the question not what she did =)

Answer 3

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

Answer 4

......

Answer 5

=)

Answer 6

Keep doing each step manually, and see where it slips up:
−7.9+8.2−3.4+2.1=−1

−7.9+8.2+(−3.4)+2.1=−1

−7.9+(−3.4)+8.2+2.1=−1

(−7.9+(−3.4))+(8.2+2.1)=−1

−11.3+10.3=−1

Answer 7

bro this one

Answer 8

Pedro deposited $35 in his savings account, then withdrew $50.

Answer 9

what about it ?

Answer 10

he cant because then he would owe the bank =)

Answer 11

its need a number line

Answer 12

so start with zero go up 35 then subtract 50 so go down to -15

Answer 13

ok bro