Dividing both sides by a common factor

Oct 13, 2025 by wbrum.org 20 views

Introduction

Exponential equations are a fundamental concept in mathematics, and solving them requires a deep understanding of algebraic manipulations and properties of exponents. In this article, we will focus on solving the equation $9^{x-6} = 729^{3(x+2)}$ using various techniques and strategies. We will break down the solution into manageable steps, providing a clear and concise explanation of each step.

Understanding the Equation

The given equation is $9^{x-6} = 729^{3(x+2)}$ . To solve this equation, we need to first understand the properties of exponents and how to manipulate them. The equation involves two exponential expressions, each with a different base. The base of the first expression is 9, while the base of the second expression is 729.

Simplifying the Equation

To simplify the equation, we can rewrite 729 as a power of 9. Since $729 = 9^3$ , we can rewrite the equation as:

9^{x-6} = (9^3)^{3(x+2)}

Using the property of exponents that $(a^m)^n = a^{mn}$ , we can simplify the right-hand side of the equation:

9^{x-6} = 9^{3(x+2) \cdot 3}

Equating Exponents

Since the bases of both expressions are the same (9), we can equate the exponents:

x-6 = 3(x+2) \cdot 3

Solving for x

To solve for x, we can start by simplifying the right-hand side of the equation:

x-6 = 9(x+2)

Expanding the right-hand side, we get:

x-6 = 9x + 18

Subtracting 9x from both sides, we get:

-10x - 6 = 18

Adding 6 to both sides, we get:

-10x = 24

Dividing both sides by -10, we get:

x = -\frac{24}{10}

Simplifying the fraction, we get:

x = -\frac{12}{5}

Conclusion

In this article, we have solved the equation $9^{x-6} = 729^{3(x+2)}$ using various techniques and strategies. We have broken down the solution into manageable steps, providing a clear and concise explanation of each step. The final solution is $x = -\frac{12}{5}$ .

Additional Tips and Strategies

When solving exponential equations, it is essential to understand the properties of exponents and how to manipulate them. Here are some additional tips and strategies to keep in mind:

Use the property of exponents that $(a^m)^n = a^{mn}$ : This property allows us to simplify complex exponential expressions.
Equating exponents: Since the bases of both expressions are the same, we can equate the exponents.
Simplifying the right-hand side: We can simplify the right-hand side of the equation by expanding and combining like terms.
Dividing both sides by a common factor: We can divide both sides of the equation by a common factor to isolate the variable.

Common Mistakes to Avoid

When solving exponential equations, there are several common mistakes to avoid:

Not simplifying the equation: Failing to simplify the equation can lead to incorrect solutions.
Not equating exponents: Failing to equate the exponents can lead to incorrect solutions.
Not simplifying the right-hand side: Failing to simplify the right-hand side of the equation can lead to incorrect solutions.
Not dividing both sides by a common factor: Failing to divide both sides of the equation by a common factor can lead to incorrect solutions.

Real-World Applications

Exponential equations have numerous real-world applications in fields such as:

Finance: Exponential equations are used to model population growth, compound interest, and inflation.
Biology: Exponential equations are used to model population growth, disease spread, and chemical reactions.
Physics: Exponential equations are used to model radioactive decay, electrical circuits, and mechanical systems.

Conclusion

In conclusion, solving exponential equations requires a deep understanding of algebraic manipulations and properties of exponents. By following the steps outlined in this article, we can solve complex exponential equations and apply them to real-world problems. Remember to simplify the equation, equate exponents, simplify the right-hand side, and divide both sides by a common factor to avoid common mistakes.

Introduction

Exponential equations can be a challenging topic for many students and professionals. In this article, we will address some of the most frequently asked questions about exponential equations, providing clear and concise answers to help you better understand this complex topic.

Q1: What is an exponential equation?

A1: An exponential equation is an equation that involves an exponential expression, which is a mathematical expression that represents a quantity that grows or decays at a constant rate. Exponential equations can be written in the form $a^x = b$ , where $a$ is the base, $x$ is the exponent, and $b$ is the result.

Q2: How do I solve an exponential equation?

A2: To solve an exponential equation, you need to isolate the variable (in this case, $x$ ) by using algebraic manipulations and properties of exponents. Here are the general steps:

Simplify the equation by rewriting the bases as powers of a common base.
Equate the exponents.
Simplify the resulting equation.
Solve for $x$ .

Q3: What is the difference between an exponential equation and a linear equation?

A3: An exponential equation involves an exponential expression, while a linear equation involves a linear expression. Exponential equations can be written in the form $a^x = b$ , while linear equations can be written in the form $ax + b = c$ .

Q4: Can I use logarithms to solve exponential equations?

A4: Yes, you can use logarithms to solve exponential equations. Logarithms are the inverse operation of exponentiation, and they can be used to solve exponential equations by converting them into linear equations.

Q5: What is the property of exponents that $(a^m)^n = a^{mn}$ ?

A5: This property states that when you raise a power to a power, you multiply the exponents. For example, $(a^m)^n = a^{mn}$ .

Q6: How do I simplify an exponential expression?

A6: To simplify an exponential expression, you can use the following properties:

$(a^m)^n = a^{mn}$
$a^m \cdot a^n = a^{m+n}$
$\frac{a^m}{a^n} = a^{m-n}$

Q7: Can I use a calculator to solve exponential equations?

A7: Yes, you can use a calculator to solve exponential equations. However, it's essential to understand the underlying mathematics and to use the calculator as a tool to verify your solutions.

Q8: What are some common mistakes to avoid when solving exponential equations?

A8: Some common mistakes to avoid when solving exponential equations include:

Not simplifying the equation
Not equating exponents
Not simplifying the right-hand side
Not dividing both sides by a common factor

Q9: How do I apply exponential equations to real-world problems?

A9: Exponential equations can be applied to a wide range of real-world problems, including:

Population growth and decay
Compound interest and finance
Radioactive decay and physics
Disease spread and epidemiology

Q10: What are some advanced topics in exponential equations?

A10: Some advanced topics in exponential equations include:

Exponential functions and their properties
Logarithmic functions and their properties
Exponential equations with multiple bases
Exponential equations with fractional exponents

Conclusion

In conclusion, exponential equations can be a challenging topic, but with practice and patience, you can master them. By understanding the properties of exponents and using algebraic manipulations, you can solve complex exponential equations and apply them to real-world problems. Remember to simplify the equation, equate exponents, simplify the right-hand side, and divide both sides by a common factor to avoid common mistakes.