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hello, so i'm currently working on a linear programme optimisation, and i was wondering if someone could help me with a bit of maths. and i need to represent abs(x) in terms of a linear equation (so no root(x^2) allowed) everyone knows what absolute(x) or |x| represents and it's pretty simple to do in your head, but I was wondering if there were any computational methods or equations for evaluating this? also i'm looking specifically for a linear method so i cant have if statements and such also are there any functions that result in x = x if x>=0, x = 0 if x<0 if so what is it called? any help is appreciated, thanks