It would be (B) because 450+200x4=2620 fence posts
Multiply the first equation by 2:
4x+10y=8
Subtract the second equation from this so the 4x cancels:
3y = -3
y = -1
Plug into first equation:
2x -5 = 4
2x = 9
x = 9/2 = 4 1/2 = 4.5
So (x,y) = (-1,4.5)
−3x + 6 = 5 | -6 (first step is: "subtract 6 from both sides" <span>)
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-3x = 5-6
-3x = -1 | /(-3) (second step is: "<span>divide by (-3) on both sides</span>" <span>)
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