Question 175527
I am going to assume that .6 is a typo and call it 6 it I am right you have your answer if wrong just follow the method and replace it with .6
:
{{{(matrix(2,2,2,8,6,3))}}}{{{(matrix(2,2,3,0,2,-1))}}}

the R1C1 element is found by 2(3)-8(2)=-10
the R1C2 element is found by 2(0)-8(-1)=8
the R2C1 element is found by 6(3)-3(2)=12
the R2C2 element is found by 6(0)-3(-1)=9
:
{{{highlight((matrix(2,2,-10,8,12,9)))}}}