Solving for x (this should be easy but somehow I keep messing it up)

  • Context: High School 
  • Thread starter Thread starter ilovemynny
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Discussion Overview

The discussion revolves around a problem from a vector geometry class that involves solving for a variable \( x \) in an algebraic expression. Participants are addressing the discrepancies between the original solution provided by the poster and the textbook answer, focusing on algebraic manipulation and simplification techniques.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Technical explanation

Main Points Raised

  • The original poster (OP) expresses confusion over their solution to an algebra problem, noting a difference between their answer and the textbook's answer.
  • One participant suggests that the OP's answer is correct but requires simplification, providing a step-by-step breakdown of the algebraic manipulation needed.
  • Another participant recommends using substitutions to simplify the expression further, indicating that this approach could make the problem easier to handle.
  • The OP acknowledges the complexity of the problem and expresses gratitude for the assistance, indicating they may have made errors in their attempts to convert their answer to match the textbook's.

Areas of Agreement / Disagreement

There appears to be no consensus on the exact steps to resolve the problem, as participants offer different methods for simplification and substitution. The OP's initial confusion remains unresolved, and while one participant affirms the correctness of the OP's answer, the discussion does not reach a definitive conclusion.

Contextual Notes

The discussion highlights the potential for errors in algebraic manipulation and the challenges of matching solutions to textbook answers. The OP's approach and the provided solutions depend on the clarity of the algebraic expressions involved.

ilovemynny
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Intro:
I'm starting college this fall. I asked one of my professors if we had a textbook and he said that there's an online version and I should read a bit of it if I wanted to.
On the first chapter they were talking about simple (I mean really simple algebra, this is a vector geometry class) but I got completely stumped on one of the problems.

I got an answer but it seems to be different from the textbook answer. I tried putting in number valves for the variable in the 2 different solution but i got different solutions. I probably did this wrong s0 can someone help me solve this I don't want to be stumped on my first week of college with the engineers >.<

Problem:
It should be uploaded on this message as an attachment.

What I Did:

called "problem my way" attachment

Supposed Answer: attachment called "answer"
 

Attachments

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You're answer is the same as the given solution. You just have to clean your expression up a bit.
[tex]x = \frac{e}{\frac{c - a}{a + 1/b} - d} - c[/tex]
Take the fraction in the denominator and multiply by [itex]\frac{b}{b}[/itex]
[tex]x = \frac{e}{\frac{b(c - a)}{ba + 1} - d} - c[/tex]
Perform the subtraction in the denominator by finding the LCD (which is ba + 1):
[tex]x = \frac{e}{\frac{b(c - a)}{ba + 1} - \frac{d(ba + 1)}{(ba + 1)}} - c[/tex]
[tex]x = \frac{e}{\frac{b(c - a) - d(ba + 1)}{ba + 1}} - c[/tex]
Multiply the entire fraction by [itex]\frac{ba + 1}{ba + 1}[/itex]
[tex]x = \frac{e(ba + 1)}{b(c - a) - d(ba + 1)} - c[/tex]


Note to mods: I don't think I'm giving too much away here. This is not in the HW subforum and the OP did show a lot of the work.
 
I find it useful to do some substitutions when solving these, you could clean up the expression given and make things a lot easier
 
Oh, THANK YOU! I tried using substitution to check but yeah since it's so messy I probably messed up somewhere. Thank you so much! This problem was really starting to freak me out. Thank you, eumayang, for cleaning it up! I tried converting my answer to the book's answer but I was really confused on how to do it.
 

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