Question

Solve by using matricies.

4x + 9y = 17
6x - 3y = 8
( ? , ? )
Write your answer as a decimal rounded to the nearest thousandth.

Answer 1

x = 1.55

y = 1.86

Explanation:

Determinant of the original matrices;

Do = -3(4) -9(6)

Do = -12 - 54

Do = -66

For Dx

Replace the answer in the first column and fine the determinant

Dy = 17(-3) - 8(9)

Dy = -51-72

Dy = -123

y = Dy/Do

y = -123/-66

y = 1.86

Get Dx

Dx = 4 (-8) - 17(6)

Dx = -32-102

Dx = -134

x = Dx/Do

x = -132/-66

x = 1.55