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Adding and subtracting rational expressions:. To add or subtract rational expressions use the addition property:. Add Fractions. Add = . Why?. Because they have the same denominator. Subtract. Subtract = . Why?. = . =. Because we need the same denominator Before we subtract.
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Adding and subtracting rational expressions: To add or subtract rational expressions use the addition property:
Add Fractions Add = Why? Because they have the same denominator
Subtract • Subtract = Why? = = Because we need the same denominator Before we subtract
If the expressions have the same (common) denominator, add or subtract the numerators, keep the same denominator, and simplify the result.
To add or subtract fractions with different denominators find the least common denominator (LCD), change each fraction so that it has that denominator then add or subtract.
Simply stated, the LCD is the least number (expression) that all denominators will divide into evenly.
To find the LCD • factor each denominator • write the different factors • give each factor the highest power to which it occurs • multiply the results
Factor each write each factor give each highest exponent multiply results (y+4)(y-4) and (y-4)² (y+4)(y-4) (y+4)(y-4)² (y+4)(y-4)² Find the LCD for y²-16 and y²-8y+16
Add : • LCD = • change each fraction to LCD • add/subtract • simplify
Add : • LCD = • change each fraction to LCD • add/subtract • simplify
Add : • LCD = • change each fraction to LCD • add/subtract • simplify
If the denominators have opposite factors, then change one of them using the 3 signs of a fraction rule.
Add: ?