Matrix in Math Level2

Test Preparation
1

<p>I just took a practice test from Princeton Review's satII math.</p>

<p>It had something matrix = A, and then asked what all the elements multiplied by 3 equaled to.</p>

<p>I thought A was just referring to the matrix, but it turns out that it was referring to the determinate of the matrix.
(so the answer was 27A, since it was a 3 by 3 matrix)</p>

<p>Do I assume that "A" is always the determinate of the matrix?
(it's been a while since I took algebra...can't remember that well)</p>

<p>And How accurate does PR's practice test measure? is it easier?</p>

2

<p>could u please post the exercise as it is written in the book ? then i'll be able to correctly answer your question</p>

3

<p>If I remember, it had all these variables starting at like P and going on. If you do the determinate rule (moving the 2 columns to the right and multiplying and adding and subtracting), you will end up with 27 in front of each variable. Thus, A = the set, 27A = when you evaluate it</p>

4

<p>Yes, if you multiply k rows by 3 (or any number), you must multiply the determinant by 3^k.</p>