SOLUTION: if two rows of a determinant are interchanged, what is true of the resulting determinant?

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Question 150529: if two rows of a determinant are interchanged, what is true of the resulting determinant?
Answer by Edwin McCravy(20060) About Me  (Show Source):
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if two rows of a determinant are interchanged, what is true of the resulting determinant?

The sign is changed.
Illustration:
abs%28matrix%282%2C2%2C2%2C-7%2C-4%2C5%29%29=2%2A5-%28-7%29%2A%28-4%29=10-28=-18
abs%28matrix%282%2C2%2C-4%2C5%2C2%2C-7%29%29=%28-4%29%2A%28-7%29%2A%28-4%29=28-10=18
In general just for a 2x2 matrix.
abs%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29=ad-bc
abs%28matrix%282%2C2%2Cc%2Cd%2Ca%2Cb%29%29=cb-da=bc-ad=+-ad%2Bbc=-%28ad-bc%29+
Edwin