Question 1082381
{{{f(x + 2)–f(x)=kf(x)}}}

{{{4(x+2)-4x=k*4x}}}

{{{4x+8-4x=k*4x}}}

{{{8=k*4x}}}

{{{k=8/(4x)}}}

{{{k=2/x}}}, expression; not a value