[confusedbuzz]

How can you solve a pair of equations with 2 variables if you've been given a matrix with the variables?
Like suppose you're given

(4 -1 )
(-3 2 )

and the two equations given are

y = 4x + 8
2y -3x + 1 = 0

[ISneezeFunny]

Confused, I'm not sure if it's because I'm hung over... but to me, that question doesn't make sense.

in the matrix, is x = (4, -3) and y = (-1, 2)? If that's the case, then that doesn't work within the equations.

You can solve the equation below even without the matrix as

y = 4x + 8

substitute
2(4x + 8) - 3x + 1 = 0
5x + 17 = 0
5x = -17
x = -17/5

not entire sure what the matrix has anything to do with it.

[confusedbuzz]

Yeah exactly. I knew how to solve it using elimination or substitution but the question gives the matrix and says to use it.

(4 -1 )
(-3 2 )

y = 4x + 8
2y -3x + 1 = 0

If you see the first term in the matrix (4), it is the x coefficient in the first equation. The second term (-1) can be the y coefficient [if you move it to the other side of the = sign].

The third term (-3) is the coefficient of x in the second equation and the fourth term (2) is the coefficient of y in the second equation.


AHHHHH I don't know :S

[ISneezeFunny]

OK OK I got it.

sorry. Had to "recover" for a bit...

if you change the two equations so that they have a constant on each side:
4x - 1 = -8
-3x + 2y = -1

then you can make a matrix

( 4 -1) (x) = (-8)
( -3 2) (y) = (-1)

then you find the inverse of the 2x2 matrix and left multiply to the (-8, -1)

[confusedbuzz]

Haha oh okay I get it now
Thanks a lot!
Sorry I can't rate its not letting me but ill be sure to do it asap