Chapter 2 - Solving Equations - 2-4 Solving Equations With Variables on Both Sides - Practice and Problem-Solving Exercises - Page 108: 52

3(x+1)=3x+3

If we need an equation where x can be any number, we need an equation that becomes identical on both sides when we simplify. When we distribute the 3 into the parenthesis on the left side of our equation, we get that 3x+3=3x+3. Because the equation is the same on both sides, this will always be true no matter what x value we choose.