The expression "|A| + |B|" represents the sum of the absolute values of two quantities, A and B. The absolute value, denoted by the vertical bars, measures the distance of a number from zero on the number line, regardless of its sign. For example, if A is -3 and B is 4, then |A| equals 3 and |B| equals 4, making the sum |A| + |B| equal to 7. This concept is commonly used in mathematics, particularly in algebra and calculus, to simplify expressions and solve equations. The absolute value ensures that both A and B contribute positively to the total, allowing for a clear understanding of their combined magnitude without regard to direction or sign.