SOLUTION: Hello, I am not good at intermediate algebra. In fact I do not understand anything and I feel about yay tall. I feel very small. Anyways here is the questions 1. Solve the system o

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Question 30859: Hello, I am not good at intermediate algebra. In fact I do not understand anything and I feel about yay tall. I feel very small. Anyways here is the questions 1. Solve the system of equations using the subtraction method...3x+y=2 and 2x-y=3. 2. Solve the system of equations using the addition (elimination) method.....9x-2y=2 and 3x+5y=5 and the next is ...Solve the equations using the addition (elimination) method... 3x-11y=9 and -9x+33y=18. My online algebra instructor is from greece and I do not understand her at all and she is horrible at spelling and she will not let us take notes what-so-ever.
Answer by Nate(3500) (Show Source):
You can put this solution on YOUR website!
1. Solve the system of equations using the subtraction method...3x+y=2 and 2x-y=3
ANSWER:
3x+y=2 original
y=-3x+2 get 'y' by itself
plug y into another equation
2x-y=3
2x-(-3x+2)=3
2x+3x-2=3
5x=5
x=1
plug the x in one of the equations
3x+y=2
3+y=2
y=-1
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2. Solve the system of equations using the addition (elimination) method.....9x-2y=2 and 3x+5y=5
ANSWER:
9x-2y=2 original
-2y=-9x+2
y=(9/2)x-1
plug y in for one of the equations
3x+5y=5
3x+5((9/2)x-1)=5
(6/2)x+(45/2)x-5=5
(51/2)x=10
x=(10)(2/51)
x=20/51
plug in the x in one of the equations:
9x-2y=2
(9)(20/51)-2y=2
(180/51)-2y=(102/51)
-2y=(-78/51)
y=(-78/51)(-1/2)
y=(78/102)
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...Solve the equations using the addition (elimination) method... 3x-11y=9 and -9x+33y=18
ANSWER:
-9x+33y=18
33y=9x+18
y=(3/11)x+(6/11)
plug in y for an equation:
3x-11y=9
3x-11((3/11)x+(6/11))=9
3x-3x-6=9
-6=9
NO SOLUTIONS BECAUSE -6 DOESN'T EQUAL 9