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3 years ago

Explain and correct the error made by a student who simplified this expression -2+7(x+8)

Mathematics

2 answers:

kenny6666 [7]3 years ago

8 0

Answer:

7x + 54

Step-by-step explanation:

Given

- 2 + 7(x + 8)

The student made the error of adding before multiplying, that is

- 2 + 7 = 5 , then multiplying (x + 8) by 5

However, multiplication is performed before addition/ subtraction, thus

- 2 + 7(x + 8) ← distribute by 7

= - 2 + 7x + 56 ← collect like terms

= 7x + 54

nalin [4]3 years ago

4 0

Answer:

The error made by the student was that they didn't distribute the 7 first, they just added -2 and 7. The correct way would be to distribute first:

-2+7(x+8)

-2+7x+56

54+7x

*Hey! Hope this helped : )*

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