SOLUTION: Solve by elimination method 3x-5y=1 6x-10y=4

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Question 743434: Solve by elimination method
3x-5y=1
6x-10y=4

Found 2 solutions by mananth, tommyt3rd:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
3.00 x -5.00 y = 1.00 .............1
Total value
6.00 x -10.00 y = 4.00 .............2
Eliminate y
multiply (1)by 2.00
Multiply (2) by 1.00
6.00 x -10.00 y = 2.00
6.00 x -10.00 y = 100.00
Add the two equations
12.00 x = 102.00
/ 12.00
x = 8.50
plug value of x in (1)
3.00 x -5.00 y = 1.00
25.50 -5.00 y = 1.00
-5.00 y = 1.00 -25.50
-5.00 y = -24.50
y = 4.90

Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
3x-5y=1
6x-10y=4

First we solve for x in the first equation
3x=1%2B5x
x=%281%2B5y%29%2F3
The second equation,
6x-10y=4
becomes...
6%28%281%2B5y%29%2F3%29-10y=4
which we simplify as follows...
2%281%2B5y%29-10y=4
2%2B10y-10y=4
2=4
this clearly a contradiction. This contradiction tells us that our system has no solution. (Whenever we arrive at a contradiction after following the solution method correctly we know that the system has no solution. If we arrive at an identity we know that the lines are coincident)