SOLUTION: Solve using addition/elimination. 1.8x-2y=.9 .04x+.18y=.15

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Question 162695: Solve using addition/elimination.
1.8x-2y=.9
.04x+.18y=.15
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve using addition/elimination.
1.8x-2y=.9
.04x+.18y=.15
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Multiply the 2nd eqn by 45
1.8x + 8.1y = 6.75
Subtract from eqn 1
0x - 10.1y = -5.85
y = 5.85/10.1 = 585/1010 = 117/202
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Sub into eqn 2
.04x + .18*117/202 = .15
4x + 18*117/202 = 15
4x + 1053/101 = 1515/101
4x = 462/101
x = 231/202
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Check:
1.8x-2y=.9
1.8*231/202 - 2*117/202 =? .9
Divide by 9
.2*231/202 - 2*13/202 =? .1
46.2/202 - 26/202 =? .1
20.2/202 is .1, so it's correct