Question

Помогите решить систему уравнений!!

Answer 1

$begin{equation*} begin{cases} x + 2y - 3z = 4, \ 2x - y + z = 5, \ -x - y + z = -3. end{cases} end{equation*}$

$begin{equation*} begin{cases} x + 2y - 3z = 4, \ 2x - y + z - (-x - y + z)= 5-(-3), \ -x - y + z = -3. end{cases} end{equation*}$

$begin{equation*} begin{cases} x + 2y - 3z = 4,\ 3x = 8, \ -x - y + z = -3 | * -3; 3x + 3y - 3z = 9. end{cases} end{equation*}$

$begin{equation*} begin{cases} x + 2y - 3z = 4 | * 3; 3x + 6y - 9z = 12,\ 3x = 8, \ 8 + 3y - 3z = 9, -3z = 1 - 3y. end{cases} end{equation*}$

$begin{equation*} begin{cases} 8 + 6y +3(1 - 3y) = 12, 6y + 3 - 9y = 4, -3y = 1 \ 3x = 8, \ -3z = 1 - 3y. end{cases} end{equation*}$

$begin{equation*} begin{cases} -3y = 1, boxed{y = -frac{1}{3}} \ 3x = 8, boxed{x = frac{8}{3}}\ -3z = 1 + (-3y) = 1 + 1 = 2, boxed{z = -frac{2}{3}} end{cases} end{equation*}$

Answer 2

3x заменили на 8

Answer 3

а точно спасибо

Answer 4

-9z = 3*(-3z) = 3*(1 - 3y)

Answer 5

На всякий пожарный.

Answer 6

спасибо вам огромное