Solve the system of equations.

3x+4y+3z=9
3x+3y+3z=3
2x+4y+3z=8

A. (x=2, y=5, z=-7)
B. (x=1, y=6, z=-6)
C. (x=0, y=7, z=-5)
D. (x=3, y=4, z=-4)

B:) x = 1 , y = 6 , z = -6

Step-by-step explanation:

Solve the following system:

{3 x + 4 y + 3 z = 9 | (equation 1)

3 x + 3 y + 3 z = 3 | (equation 2)

2 x + 4 y + 3 z = 8 | (equation 3)

Subtract equation 1 from equation 2:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x - y+0 z = -6 | (equation 2)

2 x + 4 y + 3 z = 8 | (equation 3)

Multiply equation 2 by -1:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+y+0 z = 6 | (equation 2)

2 x + 4 y + 3 z = 8 | (equation 3)

Subtract 2/3 × (equation 1) from equation 3:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+y+0 z = 6 | (equation 2)

0 x+(4 y)/3 + z = 2 | (equation 3)

Multiply equation 3 by 3:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+y+0 z = 6 | (equation 2)

0 x+4 y + 3 z = 6 | (equation 3)

Swap equation 2 with equation 3:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+4 y + 3 z = 6 | (equation 2)

0 x+y+0 z = 6 | (equation 3)

Subtract 1/4 × (equation 2) from equation 3:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+4 y + 3 z = 6 | (equation 2)

0 x+0 y - (3 z)/4 = 9/2 | (equation 3)

Multiply equation 3 by 4/3:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+4 y + 3 z = 6 | (equation 2)

0 x+0 y - z = 6 | (equation 3)

Multiply equation 3 by -1:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+4 y + 3 z = 6 | (equation 2)

0 x+0 y+z = -6 | (equation 3)

Subtract 3 × (equation 3) from equation 2:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+4 y+0 z = 24 | (equation 2)

0 x+0 y+z = -6 | (equation 3)

Divide equation 2 by 4:

{3 x + 4 y + 3 z = 9 | (equation 1)

0 x+y+0 z = 6 | (equation 2)

0 x+0 y+z = -6 | (equation 3)

Subtract 4 × (equation 2) from equation 1:

{3 x + 0 y+3 z = -15 | (equation 1)

0 x+y+0 z = 6 | (equation 2)

0 x+0 y+z = -6 | (equation 3)

Subtract 3 × (equation 3) from equation 1:

{3 x+0 y+0 z = 3 | (equation 1)

0 x+y+0 z = 6 | (equation 2)

0 x+0 y+z = -6 | (equation 3)

Divide equation 1 by 3:

{x+0 y+0 z = 1 | (equation 1)

0 x+y+0 z = 6 | (equation 2)

0 x+0 y+z = -6 | (equation 3)

Collect results:

{x = 1 , y = 6 , z = -6

step-by-step explanation:

0

x = -4

step-by-step explanation:

- 20 - 4(x + 3) = 4x

=> -20 - 4x - 12 = 4x

=> - 32 -4x = 4x

=> -32 = 4x + 4x

=> - 32 = 8x

=> -32/8 = x

=> -4 = x