Solve the Linear Equation: 5(X-8) + 1/2 = 0

Linear Equations with Distribution and Fractions

Solve for X:

5(x8)+12=0 5(x-8)+\frac{1}{2}=0

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Solve
00:04 Open brackets properly, multiply by each factor
00:20 Arrange the equation so that only the unknown X is on one side
00:28 Isolate X
00:41 And this is the solution to the question

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

Solve for X:

5(x8)+12=0 5(x-8)+\frac{1}{2}=0

2

Step-by-step solution

To solve the linear equation 5(x8)+12=0 5(x-8)+\frac{1}{2}=0 , follow these steps:

  • Step 1: Distribute the 5 across (x8) (x-8) .

The equation becomes:

5x40+12=0 5x - 40 + \frac{1}{2} = 0 .

  • Step 2: Combine the constants on the left side.

Combine 40-40 and 12\frac{1}{2}:

5x40+12=0 5x - 40 + \frac{1}{2} = 0 .

Convert 40-40 into a fraction to simplify: 40=802-40 = -\frac{80}{2}.

The equation becomes:

5x802+12=0 5x - \frac{80}{2} + \frac{1}{2} = 0 .

Simplify it to:

5x792=0 5x - \frac{79}{2} = 0 .

  • Step 3: Isolate x x .

To move 792-\frac{79}{2} to the other side, we add 792\frac{79}{2} to both sides:

5x=792 5x = \frac{79}{2} .

  • Step 4: Solve for x x .

Divide both sides by 5 to isolate x x :

x=792÷5 x = \frac{79}{2} \div 5 .

x=792×15 x = \frac{79}{2} \times \frac{1}{5} .

x=7910 x = \frac{79}{10} .

Therefore, the solution to the equation is x=7910 x = \frac{79}{10} .

3

Final Answer

7910 \frac{79}{10}

Key Points to Remember

Essential concepts to master this topic
  • Distribution Rule: Apply multiplication to every term inside parentheses first
  • Fraction Technique: Convert -40 to 802 -\frac{80}{2} when combining with 12 \frac{1}{2}
  • Check Solution: Substitute x=7910 x = \frac{79}{10} back: 5(79108)+12=0 5(\frac{79}{10} - 8) + \frac{1}{2} = 0

Common Mistakes

Avoid these frequent errors
  • Forgetting to distribute the coefficient to all terms in parentheses
    Don't multiply 5 by just x and forget the -8 = wrong equation setup! This creates 5x - 8 instead of 5x - 40, leading to completely wrong answers. Always distribute the coefficient to every single term inside the parentheses.

Practice Quiz

Test your knowledge with interactive questions

Solve for x:

\( 2(4-x)=8 \)

FAQ

Everything you need to know about this question

Why do I need to distribute 5 to both x and -8?

+

The distributive property requires you to multiply the outside number by every term inside the parentheses. So 5(x8) 5(x - 8) becomes 5x40 5x - 40 , not just 5x8 5x - 8 !

How do I combine -40 and 1/2?

+

Convert both to the same denominator! Change -40 to 802 -\frac{80}{2} , then combine: 802+12=792 -\frac{80}{2} + \frac{1}{2} = -\frac{79}{2} . This keeps everything as fractions for easier calculation.

Why is my final answer a fraction?

+

That's completely normal! Linear equations often have fractional solutions. x=7910 x = \frac{79}{10} is the exact answer, which equals 7.9 as a decimal.

How do I divide by 5 when I have a fraction?

+

Dividing by 5 is the same as multiplying by 15 \frac{1}{5} . So 792÷5=792×15=7910 \frac{79}{2} ÷ 5 = \frac{79}{2} × \frac{1}{5} = \frac{79}{10} .

Can I check my answer without substituting back?

+

Always substitute back! It's the most reliable way to catch errors. Plug x=7910 x = \frac{79}{10} into the original equation and verify both sides equal zero.

What if I get confused with all the fraction operations?

+

Take it one step at a time! First distribute, then combine like terms, then isolate x. Draw clear fraction bars and double-check your arithmetic at each step.

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Linear Equations (One Variable) questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations