SOLUTION: solve by substitution method 0.1x+0.3y=-0.7 0.9x-0.2y=8.2

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: solve by substitution method 0.1x+0.3y=-0.7 0.9x-0.2y=8.2      Log On


   

Question 531433: solve by substitution method
0.1x+0.3y=-0.7
0.9x-0.2y=8.2
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve by substitution method
0.1x+0.3y=-0.7
0.9x-0.2y=8.2
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1st: Get rid of all those decimals
x + 3y = -7
9x - 2y = 82
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Multiply the 1st equation by "9" to get:
9x + 27y = -63
9x - 2y = 82
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Subtract and solvd for "y":
29y = 145
y = 5
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Solve for "x":
x + 3y = -7
x + 15 = -7
x = -22/3
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cheers,
Stan H.
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