questions on attachment!!

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- Jul 24th 2006, 03:36 PM #1

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- Jul 24th 2006, 07:21 PM #2

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Originally Posted by**Lane**

The cofactor is times the determinant of the matrix obtained from by deleting the th row

and the th column of .

The question is asking for and .

,

where denotes something left to the reader to complete.

RonL

- Jul 24th 2006, 07:56 PM #3

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Hello, Lane1

You could help us by indicating where your difficulty lies.

Otherwise, we're not helping you ... we're just doing your homework.

1. Find the three cofactors of the second row of the matrix.

. . . .

Cofactor of

Cofactor of

Cofactor of

2. Find the determinant of:

. . .

3. Use Cramer's Rule to solve (if possible) the system of equations.

. . . .

the vertices of a triangle are given below. .Use a determinant

and the vertices of the triangle to find the area of the triangle.

. . . . .

The area of a triangle with vertices is given by:

. . .

So we have: .

I'll let*you*crank it out . . .

- Jul 24th 2006, 08:02 PM #4

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