Complete the two-column proof.
Given: x over 6 plus 2 equals 15
Prove: x = 78
x over 6 plus 2 equals 15 a. __________
x over 6 equals 13 b. __________
x = 78 c. ___________
x over 6 plus 2 equals 15 a. Given
x over 6 equals 13 b. Subtraction property of equality
x = 78 c. Multiplication property of equality