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 3 -4x - 3y = 45

Line 5 4x + y = - 13

Line 6 -2y = 32

Well, line 1 is wrong!

If you take the equation 3x + 2y + z = 11:

Subtract 3x from both sides:

2y + z = 11 - 3x

Subtract 2y from both sides:

z = 11 - 3x - 2y

This is different from z = 11 + 3x + 2y.

Hope this helps!

Secure Information

Content will be erased after question is completed.

Enter the email address associated with your account, and we will email you a link to reset your password.

Forgot your password?

Sign Up