SOLUTION: i have tried this problem four times and i keep getting the same ordered triple (2,-5,3). But when i substitute the answer in it does not work. 1) x + 2y + 2z = -2 2) 2x - y +

Algebra ->  College  -> Linear Algebra -> SOLUTION: i have tried this problem four times and i keep getting the same ordered triple (2,-5,3). But when i substitute the answer in it does not work. 1) x + 2y + 2z = -2 2) 2x - y +      Log On


   



Question 540927: i have tried this problem four times and i keep getting the same ordered triple (2,-5,3). But when i substitute the answer in it does not work.
1) x + 2y + 2z = -2
2) 2x - y + 3z = -6
3) x - 3y + 2z = -7
1) x + 2y + 2z = -2
2) (2x - y + 3z = -6)2
4x - 2y +6z = -12
x + 2y + 2z = -2
NEW 1) 5x + 8z = -14
2) (2x - y + 3z = -6)-3
3) x - 3y + 2z = -7
-6x + 3y - 9z =18
x - 3y + 2z = -7
NEW 3) -5x - 7z = 11
NEW 1) 5x + 8z = -14
z = 3
NEW 1)5x + 8z = -14
5x + 8(3) = -14
x = 2
Original 1) x + 2y + 2z = -2
2 + 2y + 2(3) = -2
2 + 2y + 6 = -2
y = -5


Found 2 solutions by stanbon, scott8148:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
i have tried this problem four times and i keep getting the same ordered triple (2,-5,3). But when i substitute the answer in it does not work.
1) x + 2y + 2z = -2
2) 2x - y + 3z = -6
3) x - 3y + 2z = -7
=========================
x = 2
y = 1
z = -3
============
Cheers,
Stan H.
============

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
mult eqn 1) by -2 and add to eqn 2) ___ -5y - z = -2 (A)

mult eqn 1) by -1 and add to eqn 3) ___ -5y = -5 ___ y = 1

substituting ___ -5(1) - z = -2 ___ z = -3

substituting ___ x + 2(1) + 2(-3) = -2 ___ x = 2