3x-2y =-1 2x+y=4?

Question

find the ordered pair solution to the follwing system of equations
1,2 2,1 1,1 2,2

Answer 1

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

Using substitution...
2x + y = 4
so
y = 4 - 2x

put that in the first equation...
3x - 2y = -1
3x - 2(4-2x) = -1
3x - 8 + 4x = -1
7x - 8 = -1
7x = 7
x = 1

Put that back in one of the equations to find y.
y = 4 - 2x
y = 4 - 2(1) = 2

So, the solution is (1, 2)

Answer 2

Elimination by addition method

3x - 2y = - 1- - - - - -Equation 1
2x + y = 4- - - - - - - Equation 2
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Multiply equation 2 by 2

2x + y = 4

2(2x + 2(y) = 2(4)

4x + 2y = 8

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3x - 2y = - 1
4x + 2y = 8
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7x = 7

7x / 7 = 7 / 7

x = 7/7

x = 1

Insert the x value into equation 2

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3x + y = 5

2(1) + y = 4

2 + y = 4

2 + y - 2 = 4 - 2

y = 2

Insert the y value into euation 2

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Check for equatio 2

2x + y = 4

2(1) + 2 = 4

2 + 2 = 4

4 = 4

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Check for equation 1

3x - 2y = - 1

3(1) - 2(2) = - 1

3 - 4 = - 1

- 1 = - 1

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The two equations balance

The solution set is { 1, 2 }

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Answer 3

superb answer: It is going like this: {3x-2y=-a million {2x+y=4 |*2 {3x-2y=-a million {4x+2y=8 You sum the kin and you get this: 7x=7 ==>x=a million y=2 So, the answer is: x=a million;y=2. it rather is the excellent answer.

Answer 4

3x-2y = -1
x = (-1+2y)/3 ---eqn 1
2x +y=4 ---eqn 2
Sub eqn 1 into 2
therefore,
2(-1+2y)/3 + y = 4
2(-1+2y) + 3y =12
-2+4y + 3y =12
7y = 14
y =2
x = (-1+4)/3 =1
Ans: 1,2