Solve the system of equations????

Question

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

Answer 1

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

2x + 4y = - 1- - - - - Equation 1
3x + y = 1- - - - - - - Equation 2
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Substitute Method

Isolate y in equation 2

3x + y = 1

Transpose 3x

3x + y - 3x = - 3x + 1

y = - 3x + 1

Insert the y value into equation 1

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2x + 4y = - 1

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

2x + (- 12x + 4) = - 1

Remove parenthesis

2x - 12x + 4 = - 1

Collect like terms

- 10x + 4 = - 1

Transpose 4

- 10x + 4 - 4 = - 1 - 4

- 10x = - 5

Divide both sides of the equation by - 10

- 10x / - 10= - 5 / - 10

x = 5/10

x = 1/2

Insert the x value into equation 1

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2x + 4y = - 1

2(1/2) + 4y = - 1

2/2 + 4y = - 1

1 + 4y = - 1

Transpose 1

1 + 4y - 1 = - 1 - 1

4y = - 2

Divide both sides of the equaion by 4

4y / 4 = - 2 / 4

y = - 2/4

y = - 1/2

Insert the y value into equation 1

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Check for equation 1

2x + 4y = - 1

2(1/2) + 4(- 1/2) = - 1

2/2 + (- 4/2) = - 1

1 - 2 = - 1

- 1 = - 1

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Check for equation 2

3x + y = 1

3I1/2) + (- 1/2) = 1

3/2 - 1/2 = 1

2/2 = 1

1 = 1

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Both equations balance

The solution set is { 1/2, - 1/2 }

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Answer 2

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

y=(1-3x)
2x+4*(1-3x)=-1
therefore
2x+4-12x=-1
-10x+4=-1
-10x=-5
x=1/2

Substituted x into equation 1
2(1/2)+4y=-1
4y=-2
y=-1/2

Therefore the complete solution is x=1/2, y=-1/2

Answer 3

ok so you have 2x+4y= -1 and 3x+y=1

first of all you can either use substitution or elimination. i would suggest elimination.

so take
3x+y=1
-3x = -3x
y=1-3x
now you substitute
2x+4 ( 1-3x)= -1
2x+4-12x= -1
-10x= -5
x= 1/2

so then you have x.
you substitue the value for x back into one of the origional equations to get y.
3x+y=1
3(1/2) +y=1
3/2 + y=1
y= -1/2

so ( 1/2, -1/2) would be your answer.

Answer 4

2x + 4y = - 1
- 12x - 4y = - 4----ADD
- 10x = - 5
x = 1 / 2

3/2 + y = 1
y = - 1/2

x = 1 / 2 , y = - 1 / 2

Answer 5

2x + 4y = -1 ------ eqn (1)
3x + y = 1 ------- eqn (2)
multiply eqn (2) by 4
12x + 4y = 4 ------- eqn(3)
subtracting eqn (1) from eqn (3)
10x = 5
x = 5/10 = 1/2
substituting this value in eqn (1)
3(1/2) + y =1
y = 1 - 3/2 = -1/2

Answer 6

2x+4y= -1....(eqn 1)
3x+y=1....(eqn 2)
Multiplying eqn 1 by 3 and eqn 2 by 2,we get
6x+12y= -3
6x+2y=2
(subtracting) 10y= -5
or y= =5/10= -1/2
Plugging y in eqn 1
2x+4*-1/2= -1
2x-2= -1
2x= -1+2=1
x=1/2
x=1/2 and y= -1/2 ans

Answer 7

3x+y=1
y=1-3x

2x + 4y = -1
2x + 4(1-3x) = -1
2x + 4 - 12x = -1
-10x = -5
x = 0.5

y = 1 - 3x
y = 1 - 3(0.5)
y = 1 - 1.5
y = -0.5