Simultaneous equations

3x + 2y = 13

x + 2y = - 1

{x = 7, y = - 4

Step-by-step explanation:

Solve the following system:

{3 x + 2 y = 13 | (equation 1)

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

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

{3 x + 2 y = 13 | (equation 1)

{0 x + (4 y) / 3 = (-16) / 3 | (equation 2)

Multiply equation 2 by 3/4:

{3 x + 2 y = 13 | (equation 1)

{0 x+y = - 4 | (equation 2)

Subtract 2 * (equation 2) from equation 1:

{3 x+0 y = 21 | (equation 1)

{0 x+y = - 4 | (equation 2)

Divide equation 1 by 3:

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

{0 x+y = - 4 | (equation 2)

Collect results:

Answer: {x = 7, y = - 4