Finding a and b to satisfy somthing, matrices problem

[mr_coffee]

Hello everyone (TD) hah, our professor has been out of town in CA all week so he hasn't taught us jack and yet we have everything due on monday. So these may be basic problems but I'm still lost. I tried putting them all together in 1 matrix and solving, and i got
1 0 .2
0 1 1
0 0 0
but it was wrong.
Find a and b such that

-5
10 = a
45

1
-1 + b
-3

0
1
6

a = ?
b = ?

Note the above groups of numbers should be in a 3x1 matrix, i just couldn't draw the symbols! and the = a, and + b should be the whole 3x1 matrix = a, and so on. Thanks!

 

[Galileo]

You can input math symbols with LaTeX code between [ tex ] and [ /tex ] tags (without the spaces). See the thread in the General Physics: https://www.physicsforums.com/showthread.php?t=8997
It's very easy, although matrices takes some typing -__-
So you have (click on the math to see the code):
$$a=\left[ \begin{array}{c}-5 \\ 10 \\45\end{array} \right]$$

The rest of your question is vague. I actually doubt you are given a if that's what the question asks you to find. You'd have to explain it clearer.