# Not double, but triple repeated functions...

Algebra Level 3

If $$f(x) = 5x - 2$$, then find the value of $$x$$ which satisfies $$f^3(x) = -20 - x$$. If $$x$$ can be expressed as an irreducible fraction $$\frac{a}{b}$$, find $$a+b$$ assuming $$a, b>0$$.

Note: $$f^3(x) = f(f(f(x)))$$, NOT $$(f(x))^3$$.

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