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40 votes
40 votes
Your friend asks you to check their work. You see the expression (8−10)2−30÷5×6+2 simplified in the following way:

Original Problem: (8−10)2−30÷5×6+2
Step 1: (−2)2−30÷5×6+2
Step 2: 4−30÷5×6+2
Step 3: 4−30÷30+2
Step 4: 4−1+2
Step 5: 3+2
Step 6: 5
Part A: Explain, using complete sentences, in which step and what specifically your friend's error was.



Part B: Correctly simplify this expression using a similar format - showing work for each step like was done above. Full credit will only be given if work shows Step 1, Step 2, Step 3, etc. as seen above.

User Cjxcz Odjcayrwl
by
2.6k points

1 Answer

20 votes
20 votes

Answer:

-38

Explanation:

He is not following the correct sequence:

Simplify the following:

(8 - 10) 2 - 30/5×6 + 2

-30/5×6 = (-30×6)/5:

(8 - 10) 2 + (-30×6)/5 + 2

30/5 = (5×6)/5 = 6:

(8 - 10) 2 - 6×6 + 2

8 - 10 = -2:

-2×2 - 6×6 + 2

-2×2 = -4:

-4 - 6×6 + 2

-6×6 = -36:

-4 + -36 + 2

-4 - 36 + 2 = 2 - (4 + 36):

2 - (4 + 36)

| 1 |

| 3 | 6

+ | | 4

| 4 | 0:

2 - 40

2 - 40 = -(40 - 2):

-(40 - 2)

| 3 | 10

| |

- | | 2

| 3 | 8:

Answer: -38

User Gembird
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2.9k points