If A=2 -2 b= 2 -2
5 -6 7 -9
how do i determine matrix b without using A-1 the hint is let b = b 1 b2 b3 b4 to write a system of equations. I first multiplied A*B to get my equations of a*b with the b1 b2 b3 b4 in them and then I set them equal to AB is this right.
I got 2b1-2b3=2
5b1-6b3=7
2b2-2b4=-2
5b2-6b4=-9

Question

If A=2 -2   b= 2 -2 
         5 -6        7  -9 
how do i determine matrix b without using A-1 the hint is let b = b 1 b2 b3 b4 to write a system of equations. I first multiplied A*B to get my equations of a*b with the b1 b2 b3 b4 in them and then I set them equal to AB is this right. 
I got 2b1-2b3=2 
5b1-6b3=7
2b2-2b4=-2
5b2-6b4=-9

amistre64 · Answer

what is it you are needing to accomplish?