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Part A: Solve each system using elimination or substitution. Show all work. Your finalanswer should be written as an ordered pair.1. -2x + 3y = -13 and 3x – 3y = 122.-9x - y = 29 and 9x +y=-29Part B: Solve each system by graphing. Your final answer should be labeled clearly.Show all work1. 2 + 3y = –12 and 4x – 3y = -32. 2 – 2y = 6 and 5x + 4y= 16r:

User Maxim Kasyanov
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1 Answer

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Part A

1, - 2x + 3y = - 13

3x - 3y = 12

We would apply the method of elimination. Since the coefficients of y in both equations are the same, we would eliminate y by adding both equations. It becomes

- 2x + 3x + 3y + - 3y = - 13 + 12

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

x + 0 = - 1

x = - 1

We would substitute x = - 1 into the first equation. It becomes

- 2(-1) + 3y = - 13

2 + 3y = - 13

3y = - 13 - 2

3y = - 15

y = - 15/3

y = - 5

The solutions are (- 1, - 5)

2. - 9x - y = 29

9x + y = - 29

We would apply the method of elimination. Since the coefficients of y in both equations are the same, we would eliminate y by adding both equations. It becomes

- 9x + 9x - y + y = 29 + - 29

- 9x + 9x - y + y = 29 - 29

0 - 0 = 0

0 = 0

Infinite number of solutions

User Shamseer K
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