8x + 9y = 9 3x - 5y = 20 a. (3.36, - 1.99) c. (0, - 1.99) b. (-1.11, 2.79) d. (3.36, 2.79)

x = 225/67, y = - 133/67 or decimal x≈3.3582 and y≈-1.9851, thus a. is the answer rounded.

Step-by-step explanation:

Solve the following system:

{8 x + 9 y = 9 | (equation 1)

3 x - 5 y = 20 | (equation 2)

Subtract 3/8 * (equation 1) from equation 2:

{8 x + 9 y = 9 | (equation 1)

0 x - (67 y) / 8 = 133/8 | (equation 2)

Multiply equation 2 by 8:

{8 x + 9 y = 9 | (equation 1)

0 x - 67 y = 133 | (equation 2)

Divide equation 2 by - 67:

{8 x + 9 y = 9 | (equation 1)

0 x+y = - 133/67 | (equation 2)

Subtract 9 * (equation 2) from equation 1:

{8 x+0 y = 1800/67 | (equation 1)

0 x+y = - 133/67 | (equation 2)

Divide equation 1 by 8:

{x+0 y = 225/67 | (equation 1)

0 x+y = - 133/67 | (equation 2)

Collect results:

Answer: {x = 225/67, y = - 133/67