Simplifying a Complex Fraction

Oct 13, 2025 by windailys.com 73 views

Introduction

In this article, we will delve into two distinct mathematical problems that require different approaches to solve. The first problem involves simplifying a complex fraction, while the second problem is a real-world scenario that requires us to use algebraic equations to find the solution. We will start by simplifying the complex fraction and then move on to the real-world problem.

Simplifying a Complex Fraction

To simplify the complex fraction $\frac{x^2-x-6}{x^2-4x+3} \div \frac{x^2-2x-8}{x^2+3x-4}=\square$ , we need to follow the order of operations (PEMDAS) and simplify each fraction separately.

Step 1: Factor the Numerators and Denominators

The first step is to factor the numerators and denominators of each fraction.

$\frac{x^2-x-6}{x^2-4x+3} = \frac{(x-3)(x+2)}{(x-3)(x-1)}$

$\frac{x^2-2x-8}{x^2+3x-4} = \frac{(x-4)(x+2)}{(x+4)(x-1)}$

Step 2: Cancel Out Common Factors

Now that we have factored the numerators and denominators, we can cancel out common factors.

$\frac{(x-3)(x+2)}{(x-3)(x-1)} \div \frac{(x-4)(x+2)}{(x+4)(x-1)} = \frac{x+2}{x-1} \div \frac{x-4}{x+4}$

Step 3: Simplify the Division

To simplify the division, we can multiply the first fraction by the reciprocal of the second fraction.

$\frac{x+2}{x-1} \div \frac{x-4}{x+4} = \frac{x+2}{x-1} \cdot \frac{x+4}{x-4}$

Step 4: Multiply the Numerators and Denominators

Now that we have the fractions multiplied, we can multiply the numerators and denominators.

$\frac{x+2}{x-1} \cdot \frac{x+4}{x-4} = \frac{(x+2)(x+4)}{(x-1)(x-4)}$

Step 5: Simplify the Expression

Finally, we can simplify the expression by multiplying out the numerators and denominators.

$\frac{(x+2)(x+4)}{(x-1)(x-4)} = \frac{x^2+6x+8}{x^2-5x+4}$

A Real-World Problem

A man has 21 coins in his pocket, all of which are dimes and quarters. If the total value of his change is $2.85, how many dimes and quarters does he have?

Step 1: Define the Variables

Let $d$ be the number of dimes and $q$ be the number of quarters.

Step 2: Write the Equation

Since the total value of the coins is $2.85, we can write the equation:

$0.10d + 0.25q = 2.85$

Step 3: Write the Equation for the Number of Coins

Since the total number of coins is 21, we can write the equation:

$d + q = 21$

Step 4: Solve the System of Equations

We can solve the system of equations by multiplying the second equation by 0.10 and subtracting it from the first equation.

$0.10d + 0.25q = 2.85$

$0.10d + 0.10q = 2.10$

Subtracting the second equation from the first equation, we get:

$0.15q = 0.75$

Dividing both sides by 0.15, we get:

$q = 5$

Step 5: Find the Number of Dimes

Now that we have found the number of quarters, we can find the number of dimes by substituting $q$ into the second equation.

$d + 5 = 21$

Subtracting 5 from both sides, we get:

$d = 16$

Conclusion

In this article, we simplified a complex fraction and solved a real-world problem involving algebraic equations. We used the order of operations (PEMDAS) to simplify the complex fraction and factored the numerators and denominators to cancel out common factors. We also used algebraic equations to solve the real-world problem and found the number of dimes and quarters the man has in his pocket.

Introduction

In our previous article, we simplified a complex fraction and solved a real-world problem involving algebraic equations. In this article, we will answer some of the most frequently asked questions related to the complex fraction and the real-world problem.

Q&A

Q: What is the order of operations (PEMDAS)?

A: The order of operations (PEMDAS) is a set of rules that tells us which operations to perform first when we have multiple operations in an expression. PEMDAS stands for:

Parentheses: Evaluate expressions inside parentheses first.
Exponents: Evaluate any exponential expressions next.
Multiplication and Division: Evaluate any multiplication and division operations from left to right.
Addition and Subtraction: Finally, evaluate any addition and subtraction operations from left to right.

Q: How do I simplify a complex fraction?

A: To simplify a complex fraction, you need to follow these steps:

Factor the numerators and denominators of each fraction.
Cancel out common factors.
Simplify the division by multiplying the first fraction by the reciprocal of the second fraction.
Multiply the numerators and denominators.
Simplify the expression by multiplying out the numerators and denominators.

Q: What is the difference between a complex fraction and a simple fraction?

A: A simple fraction is a fraction with a single numerator and a single denominator, such as 1/2. A complex fraction, on the other hand, is a fraction that contains one or more fractions in its numerator or denominator, such as (x+2)/(x-1).

Q: How do I solve a system of equations?

A: To solve a system of equations, you need to follow these steps:

Write the equations in the form ax + by = c.
Multiply the second equation by a constant to make the coefficients of one of the variables the same in both equations.
Subtract the first equation from the second equation to eliminate one of the variables.
Solve for the remaining variable.
Substitute the value of the remaining variable back into one of the original equations to solve for the other variable.

Q: What is the difference between a linear equation and a quadratic equation?

A: A linear equation is an equation in which the highest power of the variable is 1, such as 2x + 3 = 5. A quadratic equation, on the other hand, is an equation in which the highest power of the variable is 2, such as x^2 + 4x + 4 = 0.

Q: How do I find the number of dimes and quarters in a real-world problem?

A: To find the number of dimes and quarters in a real-world problem, you need to follow these steps:

Define the variables: Let d be the number of dimes and q be the number of quarters.
Write the equation: Write an equation that represents the total value of the coins.
Write the equation for the number of coins: Write an equation that represents the total number of coins.
Solve the system of equations: Solve the system of equations to find the values of d and q.

Conclusion

In this article, we answered some of the most frequently asked questions related to the complex fraction and the real-world problem. We covered topics such as the order of operations (PEMDAS), simplifying complex fractions, solving systems of equations, and finding the number of dimes and quarters in a real-world problem. We hope that this article has been helpful in clarifying any confusion you may have had.