What is the solution of the system ? Use elimination 3x -4y = -24 X + y = -1

1 answer:

3 0

Solve the following system using elimination:
{3 x - 4 y = -24 | (equation 1)
{x + y = -1 | (equation 2)

Subtract 1/3 × (equation 1) from equation 2:
{3 x - 4 y = -24 | (equation 1)
{0 x+(7 y)/3 = 7 | (equation 2)

Multiply equation 2 by 3/7:
{3 x - 4 y = -24 | (equation 1)
{0 x+y = 3 | (equation 2)

Add 4 × (equation 2) to equation 1:
{3 x+0 y = -12 | (equation 1)
{0 x+y = 3 | (equation 2)

Divide equation 1 by 3:
{x+0 y = -4 | (equation 1)
{0 x+y = 3 | (equation 2)

Collect results:

Answer: {x = -4, y = 3

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