Largest integer: 57
x + x + 1 + x + 2 = 168
3x + 3 = 168
-3 -3
3x = 165
/3 /3
x = 55
x = smallest integer = 55
x + 1 = middle integer = 55 + 1 = 56
x + 2 = largest integer = 55 + 2 = 57
Answer:
Identity property of multiplication
Step-by-step explanation:
From step 5:

Here, to solve for x so that the variable x stands alone, Alberto uses the identity property of multiplication, which justifies what he has in step 6.
Step 6:

According to the identity property of multiplication, any value you multiply by 1 gives you that same value.
Therefore, 1x = 1 × x = x.
The variable x multiplied by 1 will give you x.