Question 546400: solve the system of equations by using the substitution method
3x-4y=29
y=x-8
Found 4 solutions by mananth, MathTherapy, josgarithmetic, ikleyn:
Answer by mananth(16949)   (Show Source):
You can put this solution on YOUR website! 3 x -5 y = 29 .............1
1 y = -8 + 1 x ---------2
/ 1 =
y = -8 + 1 x
Substitute y in (1)
3 x -5 ( -8 + 1 x ) = 29
3 x + 40 + -5 x = 29
3 x -5 x = 29 -40
-2 x = -11
/ -2
x= 5.5
Plug the value of x in (1)
3 x -5 y = 29
3 * 5.5 -5 y = 29
16.5 -5 y = 29
-5 y = 12.5
/ -5
y= -2.5
m.ananth@hotmail.ca
Answer by MathTherapy(10836)  (Show Source):
You can put this solution on YOUR website!
solve the system of equations by using the substitution method
3x-4y=29
y=x-8
***************
Solutions, x= 5.5, and y= -2.5, by @mananth(16949) are WRONG!!
It's extremely mind-blogging to see how this respondent "treated" this math problem, especially since it's EXTREMELY EASY
to solve! This author can only hope that this "solution" was IGNORED by everyone, especially the person who asked for help!
Correct solution set: 
Answer by josgarithmetic(39817)  (Show Source):
Answer by ikleyn(53843)  (Show Source):
You can put this solution on YOUR website! .
In his solution, @mananth used a computer code (which he used practically in all his posts).
One of typical errors this code makes regularly is incorrect reading input data from original posts.
But @mananth never (or very rare) checks what the code produces,
so this is a source of many his faults.
Solutions of the other person, @lwsshar3, who also systematically uses a computer code,
suffer of the same deficiency.
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