SOLUTION: Which of the following expressions represents the correct expansion of the y determinant for the equations x + y = 0 x + z = 4 y + z = 0

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Question 1203741: Which of the following expressions represents the correct expansion of the y determinant for the equations
x + y = 0
x + z = 4
y + z = 0
Answer by ikleyn(52893) About Me  (Show Source):
You can put this solution on YOUR website!
.

Nothing follows in the post that I could consider as  " the following expressions ".


But even without having these non-existing  " following expressions ",  I can state that the y-determinant is  4.

It is because y-determinant is

        Det%5By%5D = det %28matrix%283%2C3%2C++1%2C0%2C0%2C++1%2C4%2C1%2C++0%2C0%2C1%29%29 = 4 + 0 + 0 - 0 - 0 - 0 = 4         (can be computed mentally).

Solved.

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    - Determinant of a 3x3 matrix
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