Question 109176
If you have the matrix {{{A=(matrix(2,2,a,b,c,d))}}} and {{{B=(matrix(2,1,d,e))}}}


Then when you multiply A and B, you get



{{{A*B=(matrix(2,2,a,b,c,d))*(matrix(2,1,d,e))=(matrix(2,1,a*d+b*e,c*d+d*e))}}}



So in this problem, they multiplied the two matrices to get the answer


{{{(matrix(2,2,-2,1,3/2,-1/2))*(matrix(2,1,8,6))=(matrix(2,1,-2*8+1*6,(3/2)*8+(-1/2)*6))=(matrix(2,1,-16+6,12-3))=(matrix(2,1,-10,9))}}}