Both. If you look at it like this: y=41-x you say x is independent and y is dependent of x (i.e. y is a function of x) For x=41-y you say y is independent and x is dependent of y (i.e. x is a...
2x + y = 7 y = x + 1 This is a simple linear system of equations, to solve it re-order and eliminate terms to solve for a single and then substitute back into the main equation rewrite y = x + 1 as x...