Solve the following matrix [ 2 8 22 ] [ 4 1 14 ] I think you need to multiply the top by negative 2 and then subtract from the bottom. but I am confused from there. 2x + 8y = 22 4x + y = 14 [ 2 8 22] [ 4 1 14] After this however I am lost.
You have to end up with a matrix that looks like this: [ 1 0 #] [ 0 1 #] Then the solutions for x and y will appear where the #'s are. We get the 0's first, then we get the 1's: Your augmented matrix is: [ 2 8 22] [ 4 1 14] Get a 0 where the 4 is: Multiply the top row through by -2 [-4 -16 -44] [ 4 1 14] Add the top row to the bottom row but leave the top row as it is: [-4 -16 -44] [ 0 -15 -30] Let's stop and simplify by dividing the top row through by -4, and the bottom row through by -15 [ 1 4 11] [ 0 1 2] Get a 0 where the 4 is: Multiply the bottom row by -4: [ 1 4 11] [ 0 -4 -8] Add the bottom row to the top row but keep the bottom row as it is. [ 1 0 3] [ 0 -4 -8] Get a 1 where the -4 is by dividing the bottom row through by -4 [ 1 0 3] [ 0 1 2] The two numbers in the right-most columnare the answers: x = 3, and y = 2 Edwin