Hello everyone i'm suppose to find a k, that will make this matrix singular, well i looked up what that ment, and it means i have to make the determinant 0. So i the matrix is:(adsbygoogle = window.adsbygoogle || []).push({});

-3 2 1

-9 8 3

(9+k) 2 0

so i found a random minor, say M13..

so i would have

-9 8

(9+k) 2

det = (-9)(2) - [8(9+k)] = -18 -72 -8k = -90 -8k;

so i want k to be 0, so i solve for k

-90 -8k = 0;

k = -90/8, i submitted it, and it was incorrect, any ideas why?

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# Homework Help: Making a matrix singular, i have to make the determinant 0, why isn't this right?>

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