Question

The incomplete work of a student to solve an equation is shown below:Step 1: 3x + 12 = 3Step 2: ?Step 3: x = −9 ÷ 3Step 4: x = −3What is the missing Step 2? 3x = 93x = 153x = −93x = −15

Answer 1

Case: Simple equations

Method:

Figuring step 2

Step 1: 3x + 12 = 3

Step 2:?

Subtract 12 from both sides

3x + 12 = 3

3x + 12 - 12 = 3 - 12

3x = -9

Step 3: x = −9 ÷ 3

Step 4: x = −3

Final answer:

3x = -9