The no. of solution of the equations 2x-3y=5 , x+2y=7 by matrix method and it's value?

1 Answer
May 6, 2018

The solution is #((x),(y))=((31/7),(9/7))#

Explanation:

The equations in the matrix form is

#((2,-3),(1,2))*((x),(y))=((5),(7))#

#A*X=B#

#X=A^-1B#

The inverse of a square matrix #((a,b),(c,d))# is

#=1/(ad-bc)((d,-b),(-c,a))#

Therefore,

#A^-1=1/(4+3)*((2,3),(-1,2))=((2/7,3/7),(-1/7,2/7))#

#((x),(y))=((2/7,3/7),(-1/7,2/7))*((5),(7))=((31/7),(9/7))#