Question

Consider the sequence of steps to solve the equation: 3(x - 4) + 5x = 9x - 36

Given = 3(x - 4) + 5x = 9x - 36
Step 1 = 3x - 12 + 5x = 9x - 36
Step 2 = 3x + 5x - 12 = 9x - 36
Step 3 =› 8x - 12 = 9x - 36
Step 4 => 8x - 8x - 12 = 9x - 8x - 36
Step 5 = 0 - 12 = x - 36
Step 6 = -12 = x - 36
Step 7 = -12 + 36 = x - 36 + 36
Step 8 = 24 = x + 0
Step 9 = 24 = x
Which property yields Step 7?

Answer 1

adding equal no. to both sides of the equation