Question 176605
1. y=2x+8
y=3x-1
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Substitute to get:
2x+8 = 3x-1
x = 9
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Since y = 2x+8, y = 2*9+8 = 26
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2. 2x-y=2
2x-2y=4
solve each for y:
 y = 2x-2
y = x-2
Substitute:
2x-2 = x-2
x = 0
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Since y = x-2, y = 0-2 = -2
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3. -x+y=2
2x+y=-1
Solve each for Y 
y = x + 2
y = -2x-1
Substitute to get:
x+2 = -2x-1
3x = -3
x = -1
Since y = x+2, y = -1+2 = 1
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Cheers,
Stan H.