In this case we've been given no values, simply to change it, so as you say I assume the line would have no y - intercept, with the gradient of c. Thanks for all your help :)
Sorry for lack of explanation, in this case dependent = λ while independent = f
so in the form y = mx + c, it would be 'λ = mf +c'
but what would the gradient be ?
c = fλ, where the dependent (y) variable is λ, and the independent variable (x) is f.
λ = c/f
c * 1/f = λ
Are you able to leave 1/f as equavalent to simply 'x', where the gradient would be c, or do you have to ensure 'x'/independent variable is actually f?