Question

Use the matrix method to solve the system of equations 2x + 4y = 8 and 6x + 3y = -3. The resulting matrix is

Answer 1

heres the options

Answer 2

2x + 4y = 8
6x + 3y = -3

becomes a matrix that looks like:
2 4 8
6 3 -3

the top row has a common factor of 2, so lets divide by 2
1 2 4
6 3 -3

the bottom row has a common factor of 3, so lets divide by 3
1 2 4
2 1 -1

make sense so far?

Answer 3

One expects the identity matrix to appear in the leftmost part of the result. This eliminates the third option.

The third column vector satisfies the given equations.