SOLUTION: Solve by the addition method: (3/4)x + (1/3)y = (3/2) (1/2)x + (5/6)y = (21/2)

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Question 327475: Solve by the addition method:
(3/4)x + (1/3)y = (3/2)
(1/2)x + (5/6)y = (21/2)
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
(3/4)x + (1/3)y = (3/2) multiply by 2.
(1/2)x + (5/6)y = (21/2) multiply by -3 & add.
1.5x+2/3y=3
-1.5x-15/6y=-63/2
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2y/3-15y/6=3-63/2
(2y*2-15y)/6=(3*2-63)/2
(4y-15y)/6=(6-63)/2
-11y/6=-57/2
-11y*2=6*-57
-22y=-342
y=-342/-22
y=171/11 ans.
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3x/4+1/3*171/11=3/2
3x/4+57/11=3/2
3x/4=3/2-57/11
3x/4=(3*11-57*2)/22
3x/4=(33-114)/22
3x/4=-81/22
3x*22=4*-81
66x=-324
x=-324/66
x=-54/11 ans.
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