Simultaneous equations using matrices

Question

Y=1-3x

y- 2x=6

solve these simultaneous equation using matrices 

Answer 1

First, put both equations in the form

 

ax + by =  c,

 

and set up the matrix from there.

 

 3x + y = 1

-2x + y = 6

 

Row 1:    3  1  1

Row 2:   -2  1  6

 

Replace (row 1) with [(row 1) - (row 2)]:

 

 5  0  -5 

-2  1   6

 

Replace (row 1) with [(1/5)(row 1)]:

 

 1  0  -1

-2  1   6

 

x = -1

-2(-1) + y = 6

y = 4