Help with matrices as systems?
The example in my book is not helping at all.

4x + 7y = 6
-5x + 3y = 1

I know my matrices are:
|4 7| |x| = |6|
|-5 3| |y| |1|

I get that much. Then, it says to write the matrix equation and it has this:
3a + 5b - 12c = 6
7b + 2c = 8
5a = 3c + 1

And I don't at all understand how they got that. Can someone explain it to me?

Question

Help with matrices as systems? 
The example in my book is not helping at all.

4x + 7y = 6
-5x + 3y = 1

I know my matrices are:
|4    7|  |x|   =   |6|
|-5  3|  |y|         |1|

I get that much. Then, it says to write the matrix equation and it has this:
3a + 5b - 12c = 6
7b + 2c = 8
5a = 3c + 1

And I don't at all understand how they got that. Can someone explain it to me?

loser66 · Answer

solve for x and y?

anonymous · Answer

That's how they got those three equations? I'm still confused...

loser66 · Answer

what is the question? what do they want you to do on the given equations?

loser66 · Answer

what is the name of the chapter in which the problem is?

anonymous · Answer

It's supposed to be writing a system as a matrix. This is an example from my book, but I'm not following it. I'm lost at the part that says "write the matrix equation" and how they got those three equations with a, b, and c as variables.

anonymous · Answer

Chapter 12: Matrices

loser66 · Answer

you misunderstood. They separate. Part A done. Part B is a new one. they want you to construct the matrix base on the given equations with variables a, b, c.

anonymous · Answer

*face palm*
I feel stupid. Thank you and sorry for wasting time with this!

loser66 · Answer

hahaha ,... it's my favorite phase. I always get that blank pot!!