Solve the set of linear equations by the matrix method. a+3b+2c= 3, 2a-b-3c= -8, 5a+2b+c=9, solve for a

Answer 1

http://www.wolframalpha.com/input/?i=%7B%7B1,3,2%7D,%7B2,-1,-3%7D,%7B5,2,1%7D%7D*%7B%7Ba%7D,%7Bb%7D,%7Bc%7D%7D+%3D+%7B%7B3%7D,%7B-8%7D,%7B9%7D%7D