5_3.pdf

Adding and subtracting rational expressions is similar to adding and subtracting standard fractions, requiring a common denominator. The Addition and Subtraction Property states that to add or subtract rational expressions, the denominators must be the same. If the denominators are the same, the numerators can be added or subtracted over the common denominator. If the denominators are not the same, the least common denominator (LCD) must be found by factoring each denominator, choosing the greatest power of each factor, and multiplying these factors together. The LCD is the least common multiple (LCM) of the denominators, ensuring it is a multiple of all denominators. Once the LCD is found, the rational expressions can be rewritten with the LCD as the denominator, allowing for addition and subtraction. It is essential to reduce the answers and be careful with negatives, especially when subtracting.