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4 votes
Solve the following systems of equation for x and y. Show your work on

how you solved for x and y
1. −4x − 2y = −12
4x + 8y = −24

2. x − y = 11
2x + y = 19

3. 5x + y = 9
10x − 7y = −18

4. −3x + 7y = −16
−9x + 5y = 16

5. −7x + y = −19
−2x + 3y = −19

6. 5x + 4y = −30
3x − 9y = −18

7. −4x + y = 6
−5x − y = 21

2 Answers

0 votes

Answer:

-1, 1

Explanation:

Khan Academy

User Timothy Clemans
by
3.5k points
4 votes

Add

2

y

to both sides of the equation.

4

x

=

12

+

2

ySolve for

x

in the first equation.

Tap for fewer steps...

Add

2

y

to both sides of the equation.

4

x

=

12

+

2

y

4

x

+

8

y

=

24

Divide each term by

4

and simplify.

Tap for fewer steps...

Divide each term in

4

x

=

12

+

2

y

by

4

.

4

x

4

=

12

4

+

2

y

4

4

x

+

8

y

=

24

Cancel the common factor of

4

.

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x

=

12

4

+

2

y

4

4

x

+

8

y

=

24

Simplify each term.

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x

=

3

y

2

4

x

+

8

y

=

24

Replace all occurrences of

x

with

3

y

2

in each equation.

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12

+

6

y

=

24

x

=

3

y

2

Solve for

y

in the first equation.

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y

=

6

x

=

3

y

2

Replace all occurrences of

y

with

6

in each equation.

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x

=

6

y

=

6

The solution to the system is the complete set of ordered pairs that are valid solutions.

(

6

,

6

)

The result can be shown in multiple forms.

Point Form:

(

6

,

6

)

Equation Form:

x

=

6

,

y

=

6

4

x

+

8

y

=

24 Answer: The answer to your ? is A

User HannaY
by
3.3k points