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4 years ago

X + y = 3 3x + 2y = 14

Mathematics

1 answer:

Zepler [3.9K]4 years ago

3 0

Answer:

x = 8 , y = -5

Step-by-step explanation:

Solve the following system:

{x + y = 3 | (equation 1)

3 x + 2 y = 14 | (equation 2)

Swap equation 1 with equation 2:

{3 x + 2 y = 14 | (equation 1)

x + y = 3 | (equation 2)

Subtract 1/3 × (equation 1) from equation 2:

{3 x + 2 y = 14 | (equation 1)

0 x+y/3 = -5/3 | (equation 2)

Multiply equation 2 by 3:

{3 x + 2 y = 14 | (equation 1)

0 x+y = -5 | (equation 2)

Subtract 2 × (equation 2) from equation 1:

{3 x+0 y = 24 | (equation 1)

0 x+y = -5 | (equation 2)

Divide equation 1 by 3:

{x+0 y = 8 | (equation 1)

0 x+y = -5 | (equation 2)

Collect results:

Answer: {x = 8 , y = -5

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