Presentation on theme: "Sums and Differences of Rational Expressions"— Presentation transcript:
1 Sums and Differences of Rational Expressions Objective: to add and subtract rational expressions
2 Rules for adding and subtracting fractions Find the least common denominator (LCD) of the fractions (that is the least common multiple of the denominators.)Express each fraction as an equivalent fraction with the LCD as the denominatorAdd or subtract and then simplify.
3 Examples Simplify The LCM of 5 = 5 • 1 and 15 = 5 • 3 is 15 2. multiplying by 1 will not change a number3.
4 Example with monomials SimplifyThe LCM of 3x2y, 12x, and 8y2 is 24x2y23.
5 Example with Polynomials SimplifyFactorThe LCM is (x + 3)(x – 3)(x – 1)