What is the solution of the system? Use elimination. 3x – 4y = 9 –3x + 2y = 9
A. (3, 9)
B. (–27, –9)
C. (–3, –6)
D. (–9, –9)

Question

Asked 4/4/2014 2:02:36 PM

Updated 6/5/2014 9:24:16 PM

4 Answers/Comments

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Flagged by yeswey [6/5/2014 9:18:03 PM]

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Geometric figure is line.

Plots:

(x from -0.36 to -0.31)

(x from -0.6 to 0.6)

-3x+y-1=0

Question

Asked 4/4/2014 2:02:36 PM

Updated 6/5/2014 9:24:16 PM

4 Answers/Comments

This conversation has been flagged as incorrect.

Flagged by yeswey [6/5/2014 9:18:03 PM]

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3

3x – 4y = 9

–3x + 2y = 9

adding up equations the result is:

-2y = 18

y = -9,

3x - 4(-9) = 9

3x + 36 = 9

3x = 9 - 36 = -27

x = -9

The solution for the system 3x – 4y = 9, –3x + 2y = 9 is (–9, –9)

–3x + 2y = 9

adding up equations the result is:

-2y = 18

y = -9,

3x - 4(-9) = 9

3x + 36 = 9

3x = 9 - 36 = -27

x = -9

The solution for the system 3x – 4y = 9, –3x + 2y = 9 is (–9, –9)

Added 6/5/2014 9:17:49 PM

This answer has been confirmed as correct and helpful.

Confirmed by yumdrea [6/5/2014 9:44:07 PM]

3

x = -4y + 4

2x + 8y = 8

using the first equation to institute x in the second equation:

2(-4y + 4) + 8y = 8

-8y + 8 + 8y = 8

-8y + 8y = 8 - 8

0 = 0

therefore, there are infinitely many solutions for the system x = -4y + 4, 2x + 8y = 8.

2x + 8y = 8

using the first equation to institute x in the second equation:

2(-4y + 4) + 8y = 8

-8y + 8 + 8y = 8

-8y + 8y = 8 - 8

0 = 0

therefore, there are infinitely many solutions for the system x = -4y + 4, 2x + 8y = 8.

Added 6/5/2014 9:19:51 PM

This answer has been confirmed as correct and helpful.

Confirmed by yumdrea [6/5/2014 9:44:23 PM]

3

3x – 4y = –24 (equation 1)

x + y = –1 multiple 4 on both sides the result is:

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

adding up equation 1 and equation 2 the result is:

7x = -28

x = -4

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

The solution for the system 3x – 4y = –24 x + y = –1 is (-4, 3)

x + y = –1 multiple 4 on both sides the result is:

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

adding up equation 1 and equation 2 the result is:

7x = -28

x = -4

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

The solution for the system 3x – 4y = –24 x + y = –1 is (-4, 3)

Added 6/5/2014 9:22:30 PM

This answer has been confirmed as correct and helpful.

Confirmed by yumdrea [6/5/2014 9:44:23 PM]

3

y = –3x + 2

y = –3x + 4

institute y in the second equation:

-3x + 2 = -3x + 4

-3x + 3x = 4 - 2

0 = 2 which is a false statement

Therefore, there are no solution for the system y = –3x + 2 y = –3x + 4.

If you graph the two lines you can tell they are parallel lines and dont have intersections (solutions)

y = –3x + 4

institute y in the second equation:

-3x + 2 = -3x + 4

-3x + 3x = 4 - 2

0 = 2 which is a false statement

Therefore, there are no solution for the system y = –3x + 2 y = –3x + 4.

If you graph the two lines you can tell they are parallel lines and dont have intersections (solutions)

Added 6/5/2014 9:24:16 PM

This answer has been confirmed as correct and helpful.

Confirmed by yumdrea [6/5/2014 9:44:33 PM]

What are the slope and y-intercept of the graph of the given equation?
y = –4x + 2

Question

Updated 4/5/2014 8:41:28 AM

1 Answer/Comment

The slope and y-intercept of the graph of the given equation y = –4x + 2 is slope = -4, y intercept = 2.

Added 4/5/2014 8:41:28 AM

This answer has been confirmed as correct and helpful.

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