Question

4 - 4y = -2 - 9x - 4y = -3

Answer 1

Answer:

x = -1/3 , y = 3/2

Step-by-step explanation:

Solve the following system:

{4 - 4 y = -2

-9 x - 4 y = -3

Express the system in standard form:

{0 - 4 y = -6

-9 x - 4 y = -3

Express the system in matrix form:

(0 | -4

-9 | -4)(x

y) = (-6

-3)

Write the system in augmented matrix form and use Gaussian elimination:

(0 | -4 | -6

-9 | -4 | -3)

Swap row 1 with row 2:

(-9 | -4 | -3

0 | -4 | -6)

Multiply row 1 by -1:

(9 | 4 | 3

0 | -4 | -6)

Divide row 2 by -2:

(9 | 4 | 3

0 | 2 | 3)

Divide row 2 by 2:

(9 | 4 | 3

0 | 1 | 3/2)

Subtract 4 × (row 2) from row 1:

(9 | 0 | -3

0 | 1 | 3/2)

Divide row 1 by 9:

(1 | 0 | -1/3

0 | 1 | 3/2)

Collect results:

Answer:  {x = -1/3 , y = 3/2