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3 years ago

PLEASE HELP!!! Needed asappp!

Mathematics

2 answers:

Tresset [83]3 years ago

6 0

Step-by-step explanation:

Add the corresponding sides of the two equations

2x=6

x=3

substitute for x

3+y=-1

y=-4

5x=10

x=2

substitute for x

2(2)+2y=-2

2y=-6

y=-3

12y=24

y=2

substitute for y

6x+5(2)=4

6x+10=4

x=-6

x=-1

Serggg [28]3 years ago

4 0

Answer:

Q3. x = 3, y = -4

Q4. x = 2, y = -3

Q5. x = -1, y = 2

Step-by-step explanation:

Since the question is asking us to solve the system using elimination/adding, that's what I'll do.

To solve by adding, we add the like terms of both equations together.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

1st question:

x + y = -1

x - y = 7

We add the first term together.

x + x = 2x

Then the second term.

y + -y = y - y = 0

Then the last term.

-1 + 7 = 6

Which becomes:

2x = 6

Then we solve the linear equation.

2x = 6

÷ 2 ÷ 2

x = 3

From the x value, we can then find y.

We can use either equation. In this example, I'll choose the first one.

x + y = -1

Substitute x = 3

3 + y = -1

-3 -3

y = -4

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

2nd question:

2x + 2y = -2

3x - 2y = 12

We add the first term together.

2x + 3x = 5x

Then the second term.

2y + - 2y = 2y - 2y = 0

Then the last term.

-2 + 12 = 10

Which becomes:

5x = 10

Then we solve the linear equation.

5x = 10

÷5 ÷5

x = 2

From the x value, we can then find y.

We can use either equation. In this example, I'll choose the first one.

2x + 2y = -2

Substitute x = 2

4 + 2y = -2

-4 -4

2y = -6

÷2 ÷2

y = -3

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

3rd question:

6x + 5y = 4

-6x + 7y = 20

We add the first term together.

6x + -6x = 6x - 6x = 0

Then the second term.

5y + 7y = 12y

Then the last term.

4 + 20 = 24

Which becomes:

12y = 24

Then we solve the linear equation.

12y = 24

÷12 ÷12

y = 2

From the x value, we can then find y.

We can use either equation. In this example, I'll choose the first one.

6x + 5y = 4

Substitute y = 2

6x + 10 = 4

-10 -10

6x = -6

÷6 ÷6

x = -1

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Andreyy89

Y = 4x - 9 and y = x-3 so the two right sides (4x-9 and x-3) must be equal

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4 years ago

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Answer:

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Step-by-step explanation:

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3 years ago

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