2x-y=5 3x+2y= -3 solve by substitution
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2x-y=5 3x+2y= -3 solve by substitution

[From: ] [author: ] [Date: 11-10-11] [Hit: ]
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I need to solve by substitution and need to state if it's independent/dependent ; consistent or inconsistent. I need to know how to do the steps because mine are coming out wrong.

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Multiply each side by 2 in 2x-y=5 you get 4x-2y=10

Add the x's y's and constants together

4x-2y=10
3x+2y=-3
7x+0y=7
7x=7 Divide each side by 7

[x=1]

Plug x into either equation
2(1)-y=5
2-y=5
Subtract 2 from each side
-y=3
Multiply each side by -1
[y=-3]

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2x-y=5 ==> y = 2x-5

3x+2y= -3 ==> 3x + 2(2x-5) = -3
7x -10 = -3
7x = 7
x = 1
y = 2-5 = -3

Solution is (x,y) = (1, -3) : independent, consistent

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2x-y=5
-y=5-2x
y=(5-2x)/(-1)
y=-5+2x
y=2x-5

3x+2y=-3
3x+2(2x-5)=-3
3x+4x-10=-3
7x-10=-3
7x=-3+10
7x=7
x=7/7
x=1

2x-y=5
2(1)-y=5
2-y=5
-y=5-2
-y=3
y=3/(-1)
y=-3

x=1 and y=-3

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X=13,y=21
1
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