SOLUTION: I also have one more problem I do not understand it is 0.3x-0.2y=4 0.4x+0.5y=-55/17 It says to solve by the elimination method and the solution is supposed to be an ordered pair

Algebra ->  Linear-equations -> SOLUTION: I also have one more problem I do not understand it is 0.3x-0.2y=4 0.4x+0.5y=-55/17 It says to solve by the elimination method and the solution is supposed to be an ordered pair      Log On


   



Question 246077: I also have one more problem I do not understand it is
0.3x-0.2y=4
0.4x+0.5y=-55/17
It says to solve by the elimination method and the solution is supposed to be an ordered pair of fractions, can anyone help me please? Thank you for your time it is appreciated

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
0.3x-0.2y=4
0.4x+0.5y=-55/17
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Multiply thru the 2nd equation by 17 to get rid of the denominator:
6.8x + 8.5y = -55
0.3x-0.2y=4
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Multiply thru both equations by 10 to get rid of the decimals:
68x + 85y = -550
3x - 2y = 40
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Let's say you want to get rid of the y-terms:
Multiply thru the 1st equation by 2 and
Multiply thru the 2nd equation by 85.
136x + 170y = -1100
255x - 170y = 3400
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Add the two equations and solve for "x":
391x = 2300
x = 2300/391
x = 100/17
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Substitute into 3x-2y=40 to solve for "y":
3(100/17)-2y = 40
300 - 34y = 680
34y = -380
y = -190/17
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Cheers,
Stan H.