A student solves the following problem:

Question

Problem:

2(x−3) + 3x = 19

Step 1: 2x − 6 + 3x = 19 Click and drag to move

Step2: (2x + 3x) −6 = 19 Click and drag to move

Step 3: 5x − 6 = 19 Click and drag to move

Step 4: 5x −6 + 6 = 19 + 6 Click and drag to move

Step 5: 5x = 25 Click and drag to move

Step 6: x = 5 Click and drag to move

What property justifies going from step 3 to step 4?

(1 point)

Answer 1

The property that justifies going from step 3 to step 4 is the Addition Property of Equality, according to which one can add the same quantity to both sides of an equation without changing its solution. In this case, 6 is added to both sides of the equation to isolate the variable x.