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1 vote
3x-2y = 14
7x+3y = 25

User Andilabs
by
4.0k points

1 Answer

3 votes

Answer:

x = 4, y = -1

Explanation:

Solve the following system:

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

{3 y + 7 x = 25 | (equation 2)

Swap equation 1 with equation 2:

{7 x + 3 y = 25 | (equation 1)

{3 x - 2 y = 14 | (equation 2)

Subtract 3/7 × (equation 1) from equation 2:

{7 x + 3 y = 25 | (equation 1)

{0 x - (23 y)/7 = 23/7 | (equation 2)

Multiply equation 2 by 7/23:

{7 x + 3 y = 25 | (equation 1)

{0 x - y = 1 | (equation 2)

Multiply equation 2 by -1:

{7 x + 3 y = 25 | (equation 1)

{0 x + y = -1 | (equation 2)

Subtract 3 × (equation 2) from equation 1:

{7 x + 0 y = 28 | (equation 1)

{0 x + y = -1 | (equation 2)

Divide equation 1 by 7:

{x + 0 y = 4 | (equation 1)

{0 x + y = -1 | (equation 2)

Collect results:

Answer: {x = 4, y = -1

User SiliconValley
by
4.0k points