Solve Equation: \frac{x}{2}+3=\frac{x+2}{3}-x

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Discussion Overview

The discussion revolves around solving the equation \(\frac{x}{2}+3=\frac{x+2}{3}-x\). Participants explore various methods for simplifying the equation, addressing the elimination of denominators, and verifying solutions. The scope includes mathematical reasoning and problem-solving techniques.

Discussion Character

  • Mathematical reasoning
  • Homework-related
  • Technical explanation

Main Points Raised

  • One participant suggests multiplying both sides by 6 to eliminate the denominators, identifying it as the least common multiple of 2 and 3.
  • Another participant points out an error in the first line of the multiplication process, indicating that the right-hand side should be adjusted.
  • A different approach is proposed, emphasizing the importance of simplifying fractions before proceeding with the solution.
  • Participants verify the solution \(x = -2\) by substituting it back into the original equation, confirming its correctness.

Areas of Agreement / Disagreement

There is no consensus on the initial steps taken to solve the equation, as participants present different methods and corrections. However, there is agreement on the final solution being valid.

Contextual Notes

Some participants' calculations contain errors or misinterpretations, and there are unresolved steps in the simplification process. The discussion reflects varying approaches to solving the equation.

headbang
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Ok have other solve Equations..
$$\frac{x}{2}+3=\frac{x+2}{3}-x$$
 
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We should get rid of those denominators...what is the smallest number we can multiply both sides by so that the denominators will be gone?
 
Ok have to be 6.. 2*3

$$\frac{2*3*x}{2}+6*3=\frac{x*2*2*3}{3}-x*6$$

$$3x+18=4x-6x$$

$$3x-4x-6x+18=$$

$$-7x=-18$$

$$7x=18$$

OK ?
 
Last edited:
headbang said:
Ok have to be 6.. 2*3

$$\frac{2*3*x}{2}+6*3=\frac{x*2*2*3}{3}-x*6$$

$$3x+18=4x-6x$$

$$3x-4x-6x+18=$$

$$-7x=-18$$

$$7x=18$$

OK ?
There's a problem in line 1. The RHS shold be
[math]\frac{(x + 2) \cdot 2 \cdot 3}{3} - 6x[/math]
 
Not quite...you did pick the correct value, the LCM of 2 and 3...but you multiplication wasn't quite right...

$$6\left(\frac{x}{2}+3\right)=6\left(\frac{x+2}{3}-x\right)$$

$$3x+18=2(x+2)-6x$$

$$3x+18=2x+4-6x$$

Try it from there...
 
headbang said:
Ok have other solve Equations..
$$\frac{x}{2}+3=\frac{x+2}{3}-x$$

My attitude is always SIMPLIFY before trying to do anything.

Each side is the sum of a fractional amount (even whole numbers are fractions with 1 as the denominator). How do you add fractions?

Then I would make use of the fact that if two fractions that have the same denominator are equal, then the numerators must be equal to (as the denominator tells you the TYPE of parts you have, if both sides have the same type of parts, then the only way that the fractions can be equal is if they have the same NUMBER of these type of parts, in other words, if the numerators are equal).
 
$$3x+18=2x+4-6x$$

$$3x-2x+6x=4-18$$

$$\frac{7x}{7}=\frac{-14}{7}$$

$$x=-2$$An other try... Is it ok?

And thank you all so much for helping me, trying to get my head around this math.. You are all worth your weight in gold...
 
Last edited:
headbang said:
$$3x+18=2x+4-6x$$

$$3x-2x+6x=4-18$$

$$\frac{7x}{7}=\frac{-14}{7}$$

$$x=-2$$An other try... Is it ok?

And thank you all so much for helping me, trying to get my head around this math.. You are all worth your weight in gold...

Your algebra looks good, but let's check your answer in the original equation:

$$\frac{-2}{2}+3=\frac{-2+2}{3}-(-2)$$

$$-1+3=0+2$$

$$2=2$$

Yes, your solution works! (Yes)
 

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