SOLUTION: Can you help me solve this problem by using addition/elmination? 1.8x-2y=0.9 0.04x+0.18y=0.15

Algebra ->  Equations -> SOLUTION: Can you help me solve this problem by using addition/elmination? 1.8x-2y=0.9 0.04x+0.18y=0.15      Log On


   

Question 227834: Can you help me solve this problem by using addition/elmination?
1.8x-2y=0.9
0.04x+0.18y=0.15
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
1.8x-2y=0.9 multiply this equation by .18
0.04x+0.18y=0.15 multiply this equation by 2 & then add them.
.324x-.36y=.162
.08x+.36y=.30
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.404x=.462
x=.462/.404
x=.231/.202 ans.
Now multiply the second equation by -45 & add them again.
1.8x-2y=.9
-1.8x-8.1y=-6.75
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-10.1y=-5.85
y=-5.85/-10.1
y=5.85/10.1 ans.
Proof:
.04*.231/.202+.18*5.85/10.1=.15
.00924/.202+1.053/10.1=.15
.0457+.1043=.15
.15=.15