Question 135207
<pre><font size = 4 color = "indigo">
    <b><i>v</i></b> = c<sub>1</sub><b><i>v<sub>1</sub></i></b> + c<sub>2</sub><b><i>v<sub>2</sub></i></b>

<b>[</b>4 5<b>]</b> = c<sub>1</sub><b>[</b>1 3<b>]</b> + c<sub>2</sub><b>[</b>4 -2<b>]</b>

<b>[</b>4 5<b>]</b> = <b>[</b>c<sub>1</sub>*1 c<sub>1</sub>*3<b>]</b> + <b>[</b>c<sub>2</sub>*4 c<sub>2</sub>*-2<b>]</b>

<b>[</b>4 5<b>]</b> = <b>[</b>c<sub>1</sub> 3c<sub>1</sub><b>]</b> + <b>[</b>4c<sub>2</sub> -2c<sub>2</sub><b>]</b>

<b>[</b>4 5<b>]</b> = <b>[</b>c<sub>1</sub>+4c<sub>2</sub>  3c<sub>1</sub>-2c<sub>2</sub><b>]</b>

Equating first components give the equation

4 = c<sub>1</sub> + 4c<sub>2</sub>

Equating second components gives the equation

5 = 3c<sub>1</sub> - 2c<sub>2</sub>

So we have this system of equations:

4 =  c<sub>1</sub> + 4c<sub>2</sub>
5 = 3c<sub>1</sub> - 2c<sub>2</sub>

Or

 c<sub>1</sub> + 4c<sub>2</sub> = 4 
3c<sub>1</sub> - 2c<sub>2</sub> = 5

Solve that system of equations and get

c<sub>1</sub> = 2, c<sub>2</sub> = 1/2

Edwin</pre>