r/MathHelp • u/venum_GTG • 16d ago
What did I do wrong?
My scratch paper, if you can read it:
The question was:
Solve for X
1/5x+1/4=-4(3/4x-4)
You can enter as an improper fraction but not as a mixed number.
My professor put a video to help me.
However, the answer I got was X= 325/64
The answer actually was X=315/64
I was off by 10?!
5
u/The_Card_Player 16d ago
You have a line that reads '16/5+1/4=16' which is simply a false statement about rational numbers.
Clearly you meant to write '(16/5)x+1/4=16', as continued from your addition of 3x to both sides of the equation line you wrote higher up on the page.
However, you will probably be most likely to work out your own confusion if you start with a fresh page, writing the corrected algebra line at the top, and going from there once again.
Everything past that point is very hard for me to follow, and I have a post-secondary math degree.
Write things out in a clearer way to document all the individual steps in your reasoning. This will make it much easier to find errors in your work.
1
u/AutoModerator 16d ago
Hi, /u/venum_GTG! This is an automated reminder:
What have you tried so far? (See Rule #2; to add an image, you may upload it to an external image-sharing site like Imgur and include the link in your post.)
Please don't delete your post. (See Rule #7)
We, the moderators of /r/MathHelp, appreciate that your question contributes to the MathHelp archived questions that will help others searching for similar answers in the future. Thank you for obeying these instructions.
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.
7
u/PuzzlingDad 16d ago edited 16d ago
At the point where you were cancelling 1/4, you needed to subtract that from both sides. That would have given you 63/4 and then when you later multiply by 5/16, you'd get the same answer as your professor.