Solving linear equations: 15 - 3x = 25 + 2x

[mathisnotfun]

the problem is 15-3x=25+2x

this is what i did
15-3x=25+2x
-3x -3x
--------------------
0x 22


15=22+2x
-22 -22
-----------------
-7 0

-7/9=-3.5 so i got x=-3.5

i know i got this wrond because i checked in on my graphing calculator by pluggin -3.5 in as x in the Y= and then went to the table and there wasn't a single y value that was the same as the one next to it for the same x value. Thanks for your help

 

[o_O]

Re: can someone please tell me what i did wrong

Graphing calculator?? Why didn't you just plug in your answer to see if both sides actually equal one another?

Your mistake is subtracting 3x from 25. You can't do that. You add/subtract like terms with like terms.

 

[Denis]

this is what i did
15-3x=25+2x
-3x -3x
--------------------
0x 22

-3x - 3x = -6x, NOT 0x

15 - 3x + 3x = 25 + 2x + 3x
15 = 25 + 5x

If you're still lost, see your teacher.

 

[Deleted member 4993]

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