SOLUTION: COULD SOME ONE HELP? SOLVE EACH SYSTEM OF SIMULTANEOUS EQUATIONS BY USING THE LINEAR COMBINATIONS METHOD. 1. 9x+3y=33 5x-y=13 solution 2. x+3y=6 2x-3y=9 solution 3. 11

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Question 148321: COULD SOME ONE HELP? SOLVE EACH SYSTEM OF SIMULTANEOUS EQUATIONS BY USING THE LINEAR COMBINATIONS METHOD. 1. 9x+3y=33 5x-y=13 solution 2. x+3y=6 2x-3y=9 solution 3. 11x-5y=4 16x=20+12y solution
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
1.
9x+3y=33
5x-y=13
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Multiply thru 2nd by 3 to get:
15y-3y=39
Add that to 1st to get:
24y = 72
y = 3
Substitute that into 2nd to solve for "x":
5x-3=13
5x=16
x =16/5
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2.
x+3y=6
2x-3y=9
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Add 1st and 2nd to get:
3x = 15
x = 5
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Substitute that into 1st to solve for "y":
5 + 3y = 6
3y = 1
y = 1/3
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3.
11x-5y=4
16x=20+12y
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Rearrange:
11x-5y = 4
16x-12y = 20
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Multiply thru 1st by 12 ;Multiply thru 2nd by 5 to get:
132x-60y = 48
80x-60y = 100
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Subtract 2nd from 1st to get:
52x = -52
x = -1
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Substitute into 11x-5y=4 to solve for "y":
-11-5y=4
5y = -15
y = -3
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Cheers,
Stan H.