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What is 2x-3y=-1
y=x-1

User Vexter
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2 Answers

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2x - 3y = -1
y = x - 1

2x - 3y = -1
2x - 3(x - 1) = -1
2x - 3(x) + 3(1) = -1
2x - 3x + 3 = -1
-x + 3 = -1
- 3 - 3
-x = -4
-1 -1
x = 4

y = x - 1
y = 4 - 1
y = 3
(x, y) = (4, 3)
User Porculus
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If you're looking for the solution to the system of equations, here's how we solve using substitution
We know that y = x - 1, so we can plug that into the first equation giving
2x - 3(x-1) = -1
Now distribute the 3 giving 2x - 3x + 3 = -1. After combining like terms we get -x + 3 = -1. Now subtract 3 from both sides, -x = -4, and multiply both sides by -1 to make x positive. x = 4
Now we can plug that into the second equation to get y
y = x - 1, and we know that x = 4, so y = 4 - 1, y = 3. The solution is (4, 3)
User Trap
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