1. Bell Ringer 12/6/18
1. What is the restriction on rational expressions which results in extraneous solutions?
2. When solving equations with fractions, what do you do to “get rid of the fraction”?

2. Solving Rational Equations
Thursday, December 6, 2018

3. A rational equation is an equation between rational expressions.
For example, and are rational equations.
#1 If you have two rational expressions set equal, you can cross multiply to solve. #2 If there is more than one term, sometimes you can combine then cross multiply. #3 If the expressions have the same denominator, just cross it out and solve.

4. Cross-Multiplying
Use when each side has a single rational expression (it’s a proportion) OR if you can make it into a proportion.
Examples:
#1 #2
#3 #4
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5. Multiply by LCD Use when you are adding or subtracting. Examples: #1#2
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6. Just “drop” the denominator
Use if the denominators are the same for every term.
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7. Assignments Classwork: Solving Rational Equations ODD
Homework: Solving Rational Equations EVEN

8. Exit Ticket When solving rational equations…
1. When can you cross out the denominators?
2. When can you cross multiply?
3. Why do you need to check your solutions?