Chapter 2: Problem 38
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$\frac{x-5}{10}-\frac{x-3}{5}=1$$
Short Answer
Expert verified
\(x = -9\)
Step by step solution
01
Simplify the Fractions
Multiply the entire equation by 10 to eliminate the denominators. This gives \(x - 5 - 2(x - 3) = 10\). Then, distribute the -2 to the terms in the parentheses to simplify further. This results in \(x - 5 - 2x + 6 = 10\).
02
Solve the equation for \(x\)
Combine like terms on the left hand side to get \(-x + 1 = 10\). Then, subtract one from both sides to move the constant over and get \(-x = 9\). Lastly, multiply through by -1 to get \(x = -9\).
03
Rewrite the equation in the form \(f(x) = 0\)
Rewrite the original equation as \(f(x) = \frac{x-5}{10} - \frac{x-3}{5} - 1\). Since \(x = -9\) is the solution, for every \(x\), \(f(x) = 0\) when \(x = -9\).
04
Verify solution graphically
Use a graphing utility to graph the function \(f(x)\). Observe that the curve of \(f(x)\) crosses the x-axis (i.e., \(f(x) = 0\)) when \(x = -9\). Thus the graphical solution verifies the algebraic solution.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Solving Equations
Solving algebraic equations is a key skill in mathematics. It involves finding the value of a variable that makes the equation true. Here is how you can approach solving an equation like \( \frac{x-5}{10} - \frac{x-3}{5} = 1 \).
- Eliminate Fractions: Multiplying through by a common denominator, in this case, 10, helps to remove fractions. This step simplifies the equation to make it easier to solve.
- Distribute Terms: After clearing fractions, distribute any terms to combine like terms carefully. In the example, this involves expanding \(-2(x-3)\) to \(-2x + 6\).
- Combine Like Terms: Group similar terms to simplify the equation. Here, combining \(x - 5 - 2x + 6\) results in \(-x + 1\).
- Isolate the Variable: Use inverse operations to solve for the variable. For instance, subtract 1 from both sides and multiply both sides by \(-1\) to get \(x = -9\).
Graphing Functions
Graphing functions is a powerful way to visualize equations and their solutions. When you graph the function derived from the equation, you can see where it meets or crosses the x-axis, representing where the function equals zero.
For instance, in the given problem, we rewrite it as a function:
For instance, in the given problem, we rewrite it as a function:
- Function Form: Express the equation as \(f(x) = \frac{x-5}{10} - \frac{x-3}{5} - 1\).
- Identify Critical Points: To understand the function's behavior, look at key points like intercepts and turning points. In this case, we particularly care about the x-intercept, where \(f(x)=0\).
- Graph the Function: Utilize a graphing calculator or software to plot this function. This visual aid helps identify the solution by showing where the graph crosses the x-axis.
Verifying Solutions Graphically
Verifying solutions graphically involves checking that an algebraic solution fits visually within the graph of the function. This step is crucial because it offers a different perspective on the solution.
- Locate the x-intercept: After graphing \( f(x) \), find where the graph intersects the x-axis. For \( f(x) \) in our example, the intersection occurs at \( x = -9 \).
- Confirm the Solution: Ensure the point where the graph crosses the x-axis matches the algebraic solution. This intersection point is the visual confirmation that \( x = -9 \) is indeed the solution.
- Benefits of Graphical Verification: Graphical verification helps verify complex solutions or those prone to algebraic error. It reinforces understanding and ensures that your work is correct.