Question

Zach submitted the work shown below when trying to simplify the expression 3 + 2(2x - 4) what mistake did he make and what is the correct simplified expression with correct steps

Answer 1

The number “2” that is a outside the brackets multiplies both of the numbers inside the brackets.

Explanation:

3+2(2x-4)

3+4x-8

4x-5

Answer 2

Zach’s mistake in this problem is that he didn’t multiply the 2 outside of the parenthesis by -4. Another mistake made was his final expression. Instead of “4 + -1,” the problem would be “4 - 1.”

Solving Zach’s equation correctly would look like:

3 + 2(2x - 4)

→ 3 + 4x - 8

Upon combining like terms:

3 + 4x - 8

→ 4x - 5

Th simplified expression of Zach’s equation would be:

→ 4x - 5