Question

A student tried to solve the following equation but made a mistake.

Step 1: 4 – 8x = -28

Step 2: -8x = -24

Step 3: x = 3



What mistake did the student make?

Answer 1

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Answer:

in Step 2, the student added 4 on the right and subtracted 4 on the left

Explanation:

In Step 2, the student subtracted 4 on the left side of the equation, but incorrectly added 4 on the right. (The same operation needs to be performed on both sides of the equation.) The correct step 2 would be ...

-8x = -32 . . . . correct step 2

x = 4 . . . . . correct step 3