Solving 5 - 7x = -16 A Step-by-Step Guide

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Hey guys! Ever found yourself staring at an equation, feeling like you're decoding an ancient scroll? Well, today, we're tackling a common algebraic problem: determining the value of a variable. Specifically, we're diving into the equation 5 - 7x = -16. Don't worry, it's not as scary as it looks! We'll break it down step-by-step, making sure you understand not just the how, but also the why behind each move. So, buckle up, and let's get started on this mathematical adventure!

Understanding the Basics of Algebraic Equations

Before we jump into solving our equation, let's quickly recap some fundamental concepts. An algebraic equation is a mathematical statement that shows the equality of two expressions. These expressions can contain numbers, variables (like our 'x'), and operations (addition, subtraction, multiplication, division, etc.). The main goal when solving an equation is to isolate the variable on one side, effectively finding its value. Think of it like a puzzle – we're trying to figure out what 'x' is hiding behind its mathematical mask.

In our case, the equation 5 - 7x = -16 tells us that the expression on the left side (5 - 7x) has the same value as the number on the right side (-16). Our mission, should we choose to accept it (and we do!), is to manipulate the equation in a way that 'x' stands alone, proudly displaying its numerical identity. To do this, we'll use the golden rule of algebra: whatever you do to one side of the equation, you must do to the other. This keeps the equation balanced, like a seesaw that needs equal weight on both sides.

Key Principles for Solving Equations

  1. The Golden Rule: As mentioned, this is the most important principle. Maintaining balance is key to finding the correct solution.
  2. Inverse Operations: To isolate the variable, we use inverse operations. Addition and subtraction are inverses, as are multiplication and division. For example, to undo adding 5, we subtract 5. To undo multiplying by -7, we divide by -7.
  3. Order of Operations (Reversed): When simplifying expressions, we typically follow the order of operations (PEMDAS/BODMAS). However, when solving equations, we often work in reverse. We deal with addition and subtraction before multiplication and division.

With these principles in mind, we're ready to tackle our equation!

Step-by-Step Solution of the Equation 5 - 7x = -16

Alright, let's get down to business and solve 5 - 7x = -16. We'll break it down into manageable steps, explaining the logic behind each one.

Step 1: Isolate the Term with the Variable

Our first goal is to get the term containing 'x' (-7x) by itself on one side of the equation. Currently, we have a '5' being added to it. To undo this addition, we'll use the inverse operation: subtraction. We'll subtract 5 from both sides of the equation.

5 - 7x - 5 = -16 - 5

This simplifies to:

-7x = -21

See what we did there? By subtracting 5 from both sides, we've successfully isolated the '-7x' term. It's like we've cleared away the underbrush to reveal the main path.

Step 2: Isolate the Variable

Now that we have -7x = -21, we need to get 'x' all by itself. Currently, 'x' is being multiplied by -7. To undo this multiplication, we'll use the inverse operation: division. We'll divide both sides of the equation by -7.

-7x / -7 = -21 / -7

This simplifies to:

x = 3

Boom! We've done it! By dividing both sides by -7, we've successfully isolated 'x' and found its value. It's like we've reached the summit and can now see the solution stretching out before us.

Step 3: Verify the Solution (Optional but Recommended)

To be absolutely sure we've got the correct answer, it's always a good idea to verify our solution. We do this by plugging the value we found for 'x' (which is 3) back into the original equation and checking if it holds true.

Original equation: 5 - 7x = -16

Substitute x = 3:

5 - 7(3) = -16

Simplify:

5 - 21 = -16

-16 = -16

It checks out! The equation holds true, confirming that x = 3 is indeed the correct solution. It's like a final seal of approval, assuring us that our mathematical journey was a success.

Common Mistakes to Avoid When Solving Equations

Solving equations is a skill that improves with practice, but it's also helpful to be aware of common pitfalls. Here are a few mistakes to watch out for:

  • Forgetting the Golden Rule: The most common mistake is only performing an operation on one side of the equation. Remember, balance is key! Always do the same thing to both sides.
  • Incorrectly Applying Inverse Operations: Make sure you're using the correct inverse operation. Adding when you should be subtracting, or multiplying when you should be dividing, will lead to the wrong answer.
  • Order of Operations Mix-Ups: As mentioned earlier, we often work in reverse order of operations when solving equations. Don't get tripped up by this!
  • Sign Errors: Pay close attention to signs (positive and negative). A small sign error can throw off the entire solution.

By being mindful of these common mistakes, you can significantly improve your equation-solving accuracy.

Tips and Tricks for Mastering Algebraic Equations

Want to become an equation-solving pro? Here are a few extra tips and tricks to help you on your way:

  • Practice, Practice, Practice: The more you practice, the more comfortable you'll become with solving equations. Work through a variety of problems to build your skills.
  • Show Your Work: Don't try to do everything in your head. Writing out each step helps you stay organized and makes it easier to spot mistakes.
  • Check Your Answers: As we demonstrated earlier, verifying your solution is a crucial step. It's a quick way to catch errors and build confidence.
  • Break Down Complex Problems: If you're facing a particularly challenging equation, try breaking it down into smaller, more manageable steps.
  • Use Visual Aids: Sometimes, visualizing the equation can help. Draw diagrams or use manipulatives to represent the problem.
  • Don't Be Afraid to Ask for Help: If you're stuck, don't hesitate to ask a teacher, tutor, or friend for assistance. Collaboration can be a powerful learning tool.

Real-World Applications of Solving Equations

You might be wondering,