Algebra: Chapter 10-4, p 442
Adding and Subtracting Rational Expressions with Like Denominators
To add or subtract rational expressions with like denominators, add or subtract the numerators, and write the sum or difference over the common denominator. DON’T FORGET TO SIMPLIFY/FACTOR THE FINAL ANSWERS!
For example:
`(4m)/3 + (5m)/3 = (4m + 5m)/3 = (9m)/3 = 3m`
and another example,
`(2x^2 + 3x – 7)/(2x + 1) + (x^2 + x – 8)/(2x+1) = (2x^2 + 3x – 7 + x^2 + x – 8)/(2x+1) = (3x^2 + 4x – 15)/(2x+1)`
Factoring the numerator we arrive at a final answer of: `((x + 3)(3x – 5))/(2x + 1)`
Here is a link from purplemath but it is more geared toward tomorrow’s lesson with different denominators.
Math-8, Chapter 9 TEST TODAY!
No homework today!