Solve for X: 18.5 - (3/9)x + (4/9)x = 13.5 Linear Equation

Linear Equations with Mixed Fraction Coefficients

Solve for X:

18.539x+49x=9.7+3.8 18.5-\frac{3}{9}x+\frac{4}{9}x=9.7+3.8

❤️ 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 Find X
00:05 Collect terms
00:26 Arrange the equation so that only the unknown X is on one side
00:42 Collect terms
00:46 Isolate X
00:59 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:

18.539x+49x=9.7+3.8 18.5-\frac{3}{9}x+\frac{4}{9}x=9.7+3.8

2

Step-by-step solution

To solve this problem, we'll follow these steps:

  • Step 1: Combine like terms.

  • Step 2: Simplify and solve for x x .

  • Step 3: Verify the solution against provided choices.

Now, let's work through each step:

Step 1: Combine like terms on the left side of the equation.
The equation is: 18.539x+49x=9.7+3.8 18.5 - \frac{3}{9}x + \frac{4}{9}x = 9.7 + 3.8 .

Combine the x x -terms: 49x39x=19x \frac{4}{9}x - \frac{3}{9}x = \frac{1}{9}x .

The equation now looks like: 18.5+19x=9.7+3.8 18.5 + \frac{1}{9}x = 9.7 + 3.8 .

Step 2: Simplify the right side of the equation.
Calculate 9.7+3.8=13.5 9.7 + 3.8 = 13.5 .
The simplified equation becomes 18.5+19x=13.5 18.5 + \frac{1}{9}x = 13.5 .

Subtract 18.5 from both sides to isolate the x x -term.
19x=13.518.5 \frac{1}{9}x = 13.5 - 18.5 .
19x=5 \frac{1}{9}x = -5 .

To solve for x x , multiply both sides by 9 (the reciprocal of 19\frac{1}{9}):
x=5×9 x = -5 \times 9 .

Therefore, the solution to the problem is x=45 x = -45 .

Step 3: Verify the solution by comparing it with the given choices.

Since the correct answer 45 -45 is the first choice on the provided list, our solution is verified.

3

Final Answer

45 -45

Key Points to Remember

Essential concepts to master this topic
  • Combine Like Terms: Add or subtract fractions with same variable first
  • Technique: 49x39x=19x \frac{4}{9}x - \frac{3}{9}x = \frac{1}{9}x before isolating variable
  • Check: Substitute x = -45 back: 18.5+19(45)=13.5 18.5 + \frac{1}{9}(-45) = 13.5

Common Mistakes

Avoid these frequent errors
  • Forgetting to combine like terms with fractions first
    Don't solve 39x \frac{3}{9}x and 49x \frac{4}{9}x separately = extra complicated steps! This leads to confusion and calculation errors. Always combine fraction terms with the same variable first: 49x39x=19x \frac{4}{9}x - \frac{3}{9}x = \frac{1}{9}x .

Practice Quiz

Test your knowledge with interactive questions

Solve for X:

\( x - 3 + 5 = 8 - 2 \)

FAQ

Everything you need to know about this question

Why do I subtract 39x \frac{3}{9}x from 49x \frac{4}{9}x ?

+

Because the original equation has minus 39x \frac{3}{9}x ! When you have 39x+49x -\frac{3}{9}x + \frac{4}{9}x , it's the same as 49x39x \frac{4}{9}x - \frac{3}{9}x .

Can I simplify 39 \frac{3}{9} and 49 \frac{4}{9} first?

+

Yes! 39=13 \frac{3}{9} = \frac{1}{3} and 49 \frac{4}{9} stays the same. But it's often easier to work with common denominators like we did here.

How do I multiply both sides by 9?

+

Multiply every term by 9. So 19x=5 \frac{1}{9}x = -5 becomes 919x=9(5) 9 \cdot \frac{1}{9}x = 9 \cdot (-5) , which gives us x=45 x = -45 .

Why is the answer negative?

+

Because we subtracted a larger number from a smaller one: 13.518.5=5 13.5 - 18.5 = -5 . Then multiplying by 9 gives us 5×9=45 -5 \times 9 = -45 .

What if I made an arithmetic error?

+

Always double-check your calculations! Verify that 9.7+3.8=13.5 9.7 + 3.8 = 13.5 and that 13.518.5=5 13.5 - 18.5 = -5 . Small mistakes lead to wrong answers.

🌟 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