I'm doing a review of fuctions, and a nagging question popped up in my mind after completing this problem. After graphing y = |x| + x, express this equation as a piece-wise function with no absolute values. I did graph it; it was simple (following is a sketch without values): ------------/ -----------/ _________/ Now the final answer included } y = 0, where x<and=0, and y = 2x, where x>0. I found the equations by looking/calculating the slope for each separate piece. However, what I do not understand is why is it x>0 INSTEAD of x>AND=0 for y = 2x. This is perhaps trivial and easy, but I don't comprehend the reason. Thanks for your patience.