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Ch. R - Algebra Review
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 1, Problem R.6.39

Determine whether each equation is an identity, a conditional equation, or a contradiction. Give the solution set. See Example 4. 4(x + 7) = 2(x + 12) + 2(x + 1)

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1
Start by expanding both sides of the equation to simplify the expressions. Use the distributive property: multiply 4 by each term inside the parentheses on the left side, and similarly multiply 2 by each term inside the parentheses on the right side.
After expanding, combine like terms on each side of the equation to simplify further. This means adding or subtracting terms with the variable \( x \) and constant terms separately.
Next, get all terms involving \( x \) on one side of the equation and all constant terms on the other side. You can do this by adding or subtracting terms from both sides to isolate \( x \).
Once \( x \) is isolated, simplify the equation to see if you get a true statement for all values of \( x \), a specific value of \( x \), or no solution. This will help determine if the equation is an identity, conditional equation, or contradiction.
Finally, based on the simplified form, state the solution set: if the equation is true for all \( x \), the solution set is all real numbers (identity); if true for specific \( x \), list those values (conditional); if no values satisfy it, the solution set is empty (contradiction).

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Types of Equations: Identity, Conditional, and Contradiction

An identity is an equation true for all values of the variable, a conditional equation is true only for specific values, and a contradiction has no solution. Recognizing these types helps determine the nature of the solution set.
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Solving Linear Equations

Solving linear equations involves simplifying both sides, combining like terms, and isolating the variable. This process helps find the values that satisfy the equation or determine if it holds for all or no values.
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Solution Sets

The solution set is the collection of all values that satisfy the equation. For identities, it includes all real numbers; for conditional equations, specific values; and for contradictions, the set is empty.
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