Word Problem: Finding a Number with -5 and 2 in the Equation

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The discussion revolves around solving a word problem that involves finding a number based on a given equation. The equation is formulated as -5n - 2 = -2n - 26. Participants suggest moving all terms involving the variable to one side and constants to the other to simplify the equation. They also recommend manipulating the equation by adding or multiplying to eliminate negatives for easier calculations. The focus remains on guiding the original poster, Cyril, through the steps to isolate the variable and solve for the number.
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The word problem: If the product of a number and -5 is reduced by 2, the result is 26 less than twice the opposite of the number. What is the number?

I wrote it out like this:
n x (-5) - 2 = 2(-n) - 26

I'm really at a loss here. Normally when there's a variable, my teacher says to get the variable alone, but when there's two that share a number, I don't know what to do besides pick random numbers and see what happens :P

Thanks in advance,
Cyril
 
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Hi Cyril! :smile:

Just shove all the n's over to the LHS, and everything else to the RHS. :wink:
 
Haha thanks :D

So add 7 to the left to get rid of the -5 and - 2 (and add it to the right of course), but how do you move the variable from the right?
 
eugh!

perhaps i'd better start you off :wink:

n x (-5) - 2 = 2(-n) - 26​

let's rewrite that as

-5n - 2 = -2n - 26 …​

carry on from there :smile:
 
Cyrilshark said:
The word problem: If the product of a number and -5 is reduced by 2, the result is 26 less than twice the opposite of the number. What is the number?

I wrote it out like this:
n x (-5) - 2 = 2(-n) - 26
It would be better to write this as -5n- 2= -2n- 26

I'm really at a loss here. Normally when there's a variable, my teacher says to get the variable alone, but when there's two that share a number, I don't know what to do besides pick random numbers and see what happens :P

Thanks in advance,
Cyril
So combine the two: add 2n to both sides, add 2 to both sides


(If you don't like negatives, you could start by multiplying both sides by -1 to get
5n+ 2= 2n+ 26. Now subtract 2n from both sides, subtract from both sides.)
 
I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...
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