math problem

pewpew

11 Jan 09, 23:35

The system of equations
2x + y + 7z = 9556
3x + y + 4z = 5899
5x + 2y + z = 3155
can be used to estimate the number of cats, x, rats, y, and lizards, z, on an island used as a nature reserve.
a. Write this system of simultaneous linear equations in matrix form.

âŽ¡                         âŽ¤âŽ¡         âŽ¤       âŽ¡          âŽ¤
|                            |   |             |         |             |
|                            |   |             |         |             |
|                            |   |             |   =    |             |
|                            |   |             |         |             |
|                            |   |             |         |             |
âŽ£                         âŽ¦âŽ£        âŽ¦     âŽ£          âŽ¦

need help :(

pewpew

11 Jan 09, 23:36

!!! Theres two more parts behind.

b. Write down the inverse matrix that can be used to solve this system of simultaneous linear equations.

c. Solve the system of simultaneous linear equations and hence estimate the number of cats, rats and lizards
on the island.

I cant even do a. .......

eagle

11 Jan 09, 23:41

$\begin{bmatrix} 2&1&7 \\ 3&1&4 \\ 5&2&1 \end{bmatrix}$ $\begin{bmatrix} x\\ y\\ z \end{bmatrix}$ $=\begin{bmatrix} 9556\\ 5889\\ 3155 \end{bmatrix}$

pewpew

11 Jan 09, 23:43

oh!! okay, i think i know how to do b and c now.

xstryker

11 Jan 09, 23:44

mai bullshit la pewpew