Question 632892
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Hi,
Note: Post each question separately, not necessary to use pictures,
just list Eqs with the following instructions:
Solve the system of equations by using the inverse of the coefficient matrix.
 x+2y = -12
2x+2y = -16                               
{{{A =( matrix(2,2,1,2,2,2))}}} = -2  
{{{adjA = (matrix(2,2,2,-2,-2,1))}}} 
{{{A^(-1)}}} = (1/-2){{{(matrix(2,2,2,-2,-2,1)) }}}

{{{A^(-1) =  (matrix(2,2,-1,1,1,-1/2)) }}}
and...
{{{(matrix(2,1,x,y))= (matrix(2,2,-1,1,1,-1/2))(matrix(2,1,-12,-16))= (matrix(2,1,-4,-4)) }}}
Ordered pair (-4,-4) the solution for this system of equations
Checking our answer using the Elimination Method:
 x+2y = -12
2x+2y = -16   |Subtracting 1st EQ from the 2nd
  x = -4   and y = -4  as {{{-4 +2*(-4) = -12}}}
(x,y) Ordered pair (-4,-4) the solution for this system of equations