diketahui A= [ a 2 b 4] dan B = [ -1 2 c -1] dan c= [ 4 2 9-2] serta AB=C maka nilai 2a + b-2c=

[tex] \left[\begin{array}{ccc}-a+2c&2a-2\\-b+4c&2b-4\end{array}\right] [/tex]
2a-2=0
2a=2
a=2/2=1

2b-4=-2
2b=-2+4
2b=2
b=2/2=1

-a+2c=4
-1+2c=4
2c=4+1
2c=5
c=5/2

2a+b-2c=2.1+1-2.5/2=2+1-5=-2