Question 864648:  Find C=-3A+6B,  
A={-3 5 -6} {9 -5 3}    B={-2 6 7}{2 -1 -6} 
 Answer by richwmiller(17219)      (Show Source): 
You can  put this solution on YOUR website! C=-3A+6B; 
 A={{-3, 5, -6}, {9, -5, 3}}  
 B={{-2, 6, 7},{2, -1, -6}} 
answer 
{{-3, 21, 60}, 
 {-15, 9, -45}} 
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