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3 years ago

Problem 1 3x + y = –14 -2x-y=9

Mathematics

1 answer:

Radda [10]3 years ago

3 0

Answer:

x = -5 , y = 1

Step-by-step explanation:

Solve the following system:

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

-2 x - y = 9 | (equation 2)

Add 2/3 × (equation 1) to equation 2:

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

0 x - y/3 = (-1)/3 | (equation 2)

Multiply equation 2 by -3:

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

0 x+y = 1 | (equation 2)

Subtract equation 2 from equation 1:

{3 x+0 y = -15 | (equation 1)

0 x+y = 1 | (equation 2)

Divide equation 1 by 3:

{x+0 y = -5 | (equation 1)

0 x+y = 1 | (equation 2)

Collect results:

Answer: {x = -5 , y = 1

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