Cogito
Algebra 2 · Chapter 4 · Lesson 2
Adding and Simplifying Rational Expressions
Common denominators, with letters.
11 problems · about 23 minutes · A-APR.D.7
Figure — use these to answer the problems
Warm Up
Straightforward practice. Get the method working first.
4 problems(x² − 36)/(x − 6) simplifies to x + what?
Answer(x² − 25)/(x − 5) simplifies to x + what?
AnswerCan the x values in (x + 2)/(x + 7) cancel? 1 for yes, 0 for no.
Answer(x² − 1)/(x + 1) simplifies to x − what?
Answer
Build It Up
The same ideas with more to keep track of.
3 problems1/x + 1/x. What is the numerator over x?
AnswerFor 5/(x − 6), which x is excluded?
Answer(3/x) × (x/4). Result as a decimal?
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsOrder the steps for simplifying a rational expression.
Write 1 to 3 in the boxes to put these in order.
- Factor the numerator and denominator
- Note the excluded values
- Cancel shared factors
Does cancelling restore the excluded value? 1 for yes, 0 for no.
AnswerSimplifying
(x² − 4)/(x − 2) simplifies to x + what?
AnswerThe Excluded Value
For that expression, which x is excluded?
Answer