Algebra 2 help!!!?

Question

I need help with these 2 problems: 

{-3x-2y-2z = -9 
{ Z=8 
{-2x-2y-2z = -14 


{x+3y+3z = -4 
{-2x-5y+z = 1 
{3x+5z = -8

Answer 1

1)

-3x-2y-2z = -9                  -------------- (1)

z = 8                               -------------- (2)

-2x-2y-2z = -14                 -------------- (3)

(3) ⇒ 2y = 14 - 2x - 2z      -------------- (4)

Substitute 2y = 14 - 2x - 2z in equation(1)

- 3x - ( 14 - 2x - 2z ) - 2z = -9

- 3x - 14 + 2x + 2z - 2z = -9

- x = - 9 + 14

x = - 5

Substitute x = - 5 , z = 8  in equation(4)

2y = 14 - 2(-5) - 2(8)

2y = 14 + 10 - 16

2y = 8

y = 4

Solution :

x = - 5

y = 4

z = 8

Answer 2

2)

x + 3y + 3z = -4                  -------------- (1)

- 2x - 5y + z = 1                  -------------- (2)

3x + 5z = -8                        -------------- (3)

5*(1)   ⇒  5x + 15y + 15z = -20

3*(2)   ⇒ -6x -  15y +   3z = 3

ADDITION ___________________

                   - x + 18z = -17

x = 18z + 17                      -------------- (4)

Substitute x = 18z + 17 in equation(3)

3(18z + 17) + 5z = - 8

54z + 51 + 5z = -8

59z = - 8 - 51

59z = - 59

z = -1

Substitute z = -1 in equation(4)

x = 18(-1) + 17

x = - 18 + 17

x = -1

Substitute x = - 1 , z = -1  in equation(1)

-1 + 3y + 3(-1) = -4

3y - 4 = -4

3y = - 4 + 4

3y = 0

y = 0

Solution :

x = - 1

y = 0

z = - 1