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.Com
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
--------------
A) Line 1
B) Line 3
C) Line 5
D) Line 6

Found 2 solutions by ikleyn, fractalier:
Answer by ikleyn(52796)   (Show Source): You can put this solution on YOUR website!
.
First mistake is in Line 1.


Answer by fractalier(6550)   (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.

RELATED QUESTIONS

In which line is the first mistake made when solving this equation? 2x + y -­ 2z = 23 (answered by ikleyn)
Hello thanks in advanced. In which line is a mistake first made when solving the... (answered by rothauserc)
Thanks! In which line is a mistake first made when solving the following system of... (answered by ValorousDawn,Boreal)
In which line is a mistake first made when solving the following system of equations by... (answered by ikleyn,fractalier)
Thanks in advanced! in which line is a mistake first made when solving the following... (answered by Alan3354)
Expectations As this is a fundamental "hands on" course, it is expected that you master... (answered by ewatrrr)
Solve the system of equations. 2x-y+z=3 x+3y-2z=11... (answered by jim_thompson5910)
I need help solving a system of 4 equations with 4 unknowns (finding where they all... (answered by fractalier)
1. What is the formula for the determinant of a 3 x 3 matrix ? A. B.... (answered by richard1234)