A student solves the following problem: 2(x - 2) + 5x = 24

Question

Step 1: 2x - 4 + 5x = 24

Step 2: 10x - 4 = 24

Step 3: 10x - 4 + 4 = 24 + 4

Step 4: 10x = 28

Step 5: 10x/10=28/10

Step 6: x = 2.8



Where is the mistake? What did the student do incorrectly?

Answer 1

The student made a mistake in step 3. They added 4 to both sides of the equation, which is incorrect. The correct operation should be to add 4 to both sides of the equation to get:

10x - 4 + 4 = 24 + 4

This simplifies to:

10x = 28

By adding 4 to both sides, the student made an error in their calculations.

Answer 2

Step 2