help me Please
Solve this equation
{3x+y+2z=6
{x+y+4z=3
{2x+3y+2z=2
3x + y + 2z = 6 (1)
x + y + 4z = 3 (2)
2x + 3y + 2z = 2 (3)
Manuel....we can use the first two equations....write them as
y = -3x - 2z + 6
y = - x - 4z + 3 subtract the first equation from the second
0 = 2x - 2z - 3
2x = 2z + 3 (4)
Multiply the second equation by 2
2x + 2y + 8z = 6 (5)
Put (4) into (3) and (5) for 2x
(2z + 3) + 3y + 2z = 2 ⇒ 3y + 4z = -1 (6)
(2z + 3) + 2y + 8z = 6 ⇒ 2y + 10z = 3 (7)
Multiply (6) by 2 and (7) by -3
6y + 8z = -2
-6y - 30z = -9 add these
-22z = - 11 divide both sides by -22
z = 1/2
Using (4) 2x = 2z + 3
2x = 2(1/2) + 3
2x = 4
x = 2
And using (7) 2y + 10z = 3
2y + 10 (1/2) = 3
2y + 5 = 3
2y = -2
y = -1
So .... { x, y, z } = { 1/2, -1, 2 }