Hello, Lane,Originally Posted byLane

use Cramer's rule:

. So it's answer C.

Greetings

EB

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- July 23rd 2006, 06:28 PM #1

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- July 23rd 2006, 09:30 PM #2

- July 23rd 2006, 09:35 PM #3

- July 23rd 2006, 09:52 PM #4
## problem nr. 2 only

Originally Posted by**Lane**

(I assume that there is a typo in the first row)

Calculate: R2-2*R1 and R3-R1. You'll get:

Now calculate R3+4*R2:

So you get z = -1. Now re-substitute this value into equation 2 and afterward plug in the values for y and z into the first equation. You should get: [4, -5, -1]

Greetings

EB

- July 23rd 2006, 10:56 PM #5

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## Problem #3 only

The augmented matrix is equivalent to the system of equations:

Now check the candidate solutions to see which satisfy these equations.

The first equation is satisfied by those candidate solutions with , and the second by those candidates with , so it looks like (C) is the required answer.

RonL

- July 23rd 2006, 11:07 PM #6

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