Adding and Subtracting rational expressions Sec: 9.2 Sol: AII.2
With like denominators If you are adding and subtracting two rational expressions with the same denominator you simply add or subtract their numerators. Then place the results over the common denominator. Let a, b, and c be expressions with c≠0. Property: Addition Subtraction
Examples:
Adding or Subtracting with unlike Denominators Steps: 1. Find the common denominator 2. Write using common denominator 3. Add and subtract Let a, b, c, and d be expressions with c≠0 and d≠0 Addition Subtraction
Find a Least Common Multiple (LCM) For: 5x 2 – 45 and 4x x + 36 Step 1: Factor LCM:
Examples: Step 1: Factor Step 2: Find LCM Step 3: Multiply the top and bottom by what is needed. Step 4: Addition or Subtract
Simplify Complex Fractions A complex fraction is a fraction that contains a fraction in its numerator or denominator. Step 1: Multiply the numerator and denominator by the LCM of each fraction in the Numerator and denominator. Step 2: Then simplify.
Examples:
Classwork 1. 4ab 2, 42bc 3, 18a 2 c 2. x 2 +3x, 10x x -15 Simplify
Homework Pg – 40 even