In Exercises 71–78, solve each equation. Then determine whether the equation is an identity, a conditional equation, or an inconsistent equation. 5x + 9 = 9(x + 1) - 4x
Table of contents
- 0. Review of Algebra4h 18m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations1h 43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 5m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 22m
- 10. Combinatorics & Probability1h 45m
1. Equations & Inequalities
Rational Equations
Problem 103
Textbook Question
Solve: x/(x−3)=2x/(x−3)−5/3
Verified step by step guidance1
Start by observing the equation: \(\frac{x}{x-3} = \frac{2x}{x-3} - \frac{5}{3}\). Notice that the denominators on the left and right sides involve \(x-3\), so we should consider the domain restriction \(x \neq 3\) to avoid division by zero.
To eliminate the denominators, multiply both sides of the equation by the least common denominator (LCD). The denominators are \(x-3\) and 3, so the LCD is \$3(x-3)\(. Multiply every term by \)3(x-3)$:
\[3(x-3) \cdot \frac{x}{x-3} = 3(x-3) \cdot \frac{2x}{x-3} - 3(x-3) \cdot \frac{5}{3}\]
Simplify each term by canceling the denominators:
\[3x = 3 \cdot 2x - 5(x-3)\]
Now, expand and simplify the right side:
\[3x = 6x - 5x + 15\]
Combine like terms on the right side:
\[3x = (6x - 5x) + 15 = x + 15\]
Finally, isolate \(x\) by subtracting \(x\) from both sides:
\[3x - x = 15\]
Simplify the left side:
\[2x = 15\]
At this point, you can solve for \(x\) by dividing both sides by 2.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Solving Rational Equations
Rational equations involve expressions with variables in the denominator. To solve them, identify common denominators and eliminate fractions by multiplying both sides accordingly. This simplifies the equation to a polynomial form, making it easier to solve.
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Introduction to Rational Equations
Restrictions on the Domain
When solving equations with variables in denominators, certain values can make the denominator zero, which is undefined. Identifying these restrictions is crucial to exclude invalid solutions from the final answer.
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Domain Restrictions of Composed Functions
Combining Like Terms and Simplifying
After clearing denominators, combine like terms on each side to simplify the equation. This step helps isolate the variable and solve the resulting linear or polynomial equation efficiently.
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Adding & Subtracting Like Radicals
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