LESSON 2-2 17. The solution of 3x + 15 = 6x is shown below. What property justifies Step 1 in the solution? 3x + 15 = 6x Original equation 3x - 3x + 15 = 6x - 3x ? 15 = 3x Combine like terms. 5 = x Division Property of Equality A. Addition Property of Equality B. Subtraction Property of Equality C. Distributive Property D. Commutative Property of Addition