SOLUTION: Solve for x and y: 8x+5y=5 7x+10y=-1

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Question 462921: Solve for x and y:
8x+5y=5
7x+10y=-1
Found 2 solutions by stanbon, MathLover1:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x and y:
8x+5y=5
7x+10y=-1
----
Multiply thru the 1st equation:
16x + 10y = 10
7x + 10y = -1
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Subtract and solve for "x":
9x = 11
x = 11/9
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Solve for "y":
3x + 5y = 5
3(11/9) + 5y = (45/9)
-------
5y = 12/9
y = 12/45
---
y = 4/15
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Cheers,
Stan H.
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Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

8x%2B5y=5....1...both sides multiply by 2 and you will get 16x%2B10y=10
7x%2B10y=-1.......2
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16x%2B10y=10.........1
-
7x%2B10y=-1...........2....subtract 2 from 1
------------------------------
16x-7x%2B10y-10y=10-%28-1%29
9x%2Bcross%2810y%29-cross%2810y%29=10%2B1
9x=11
x=11%2F9
x=1.2222222222222222222222222222222

x=1.222
now find y
7%281.22%29%2B10y=-1
8.54%2B10y=-1
10y=-1-8.54

10y=-9.54
y=-9.54%2F10
y=-0.954
check:

8x%2B5y=5....1
8%281.222%29%2B5%28-0.954%29=5
9.77-4.77=5
5=5