Answer:
Step 5
Step-by-step explanation:
The mistake is in step 5.
The previous step was
The order operations, PEDMAS, must be applied:
We have Addition and Division here,
Using PEDMAS, we must divide first to get:
We can now add to get:
Therefore the mistake occurred at step 5
Answer: Choice B)
We have some value m and we're squaring it to get
To undo this and isolate m, we apply the square root to both sides
There are two solutions here. This is similar to how there are two solutions in something like (those two solutions being x = 5 and x = -5). Squaring any negative number leads to a positive result because
negative times negative = positive.