SOLUTION: A student is solving the system of equations below. In which line is a mistake first made? 2x + y -­ 2z = 23 3x + 2y + z = 11 x -­ y + z = ­-2 Line 1 z = 11 + 3x + 2y

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A student is solving the system of equations below. In which line is a mistake first made? 2x + y -­ 2z = 23 3x + 2y + z = 11 x -­ y + z = ­-2 Line 1 z = 11 + 3x + 2y       Log On


   

Question 1023386: A student is solving the system of equations below. In which line is a mistake first made?
2x + y -­ 2z = 23
3x + 2y + z = 11
x -­ y + z = ­-2
Line 1 z = 11 + 3x + 2y
Line 2 2x + y ­- 2(11 + 3x + 2y) = 23
Line 3 ­-4x ­- 3y = 45
Line 4 x -­ y + (11 + 3x + 2y) = ­- 2
Line 5 4x + y = - ­13
Line 6 ­-2y = 32
Line 7 y = ­16, x = ¾, z = ­-11/4
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A) Line 1
B) Line 3
C) Line 5
D) Line 6
Found 2 solutions by ikleyn, fractalier:
Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.
First mistake is in Line 1.


Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
I'm thinking the first mistake is in line 1. If you solve the second equation for z, you should get
z = 11 - 3x - 2y
Choice A.