Common Algebra Mistakes
Example: Failure to Distribute Minus Sign

The Goal

Simplify the expression:

goal


The Mistake

Find the algebra mistake:

mistake


Need a hint? Look carefully at the red part of the algebra:

mistake


The Correction

correction


An Explanation

The minus sign must be distributed across all terms inside the parentheses: -(2x + 1) = -2x - 1.

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