1. The problem statement, all variables and given/known data Solve the following linear equations simultaneously by the Least Squares solution and calculate the residuals. 2. Relevant equations 3x + 2y + z = 5 x + 6y - z = -7 x - y + 2z = 3 5x - 2y = 1 3. The attempt at a solution This is a question from this guy at work who is studying to be a surveyor. He knows me as the "Maths Genius" because I recently finished high school and got Valedictorian. He is really old and doesn't really get computers/internet. However I didn't learn this sort of thing in high school, and after watching this [http://www.youtube.com/watch?v=8mAZYv5wIcE]khanacademy[/test] vid, I only understood the Matrix forms but know nothing of the A transpose. Any help is appreciated.