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How do you perform this: 2x+3y=25 3x+4y=22

User Thales MG
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1 Answer

6 votes

Answer:

x = -34 , y = 31

Step-by-step explanation suing Gaussian elimination:

Solve the following system:

{2 x + 3 y = 25

3 x + 4 y = 22

Express the system in matrix form:

(2 | 3

3 | 4)(x

y) = (25

22)

Write the system in augmented matrix form and use Gaussian elimination:

(2 | 3 | 25

3 | 4 | 22)

Swap row 1 with row 2:

(3 | 4 | 22

2 | 3 | 25)

Subtract 2/3 × (row 1) from row 2:

(3 | 4 | 22

0 | 1/3 | 31/3)

Multiply row 2 by 3:

(3 | 4 | 22

0 | 1 | 31)

Subtract 4 × (row 2) from row 1:

(3 | 0 | -102

0 | 1 | 31)

Divide row 1 by 3:

(1 | 0 | -34

0 | 1 | 31)

Collect results:

Answer: {x = -34 , y = 31

User Haseeb Saeed
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