Finding the real roots of an $n$-th degree polynomial with 2 terms

Question

Is it possible to find the real roots of the polynomial of this form $ax^n+bx^{n-1}+c = 0$?

If $c=0$, this would be trivial, but I am not sure how to handle this case...

Edit: It is known that all coefficients are real and $a < 0$, $b>0$, $b = |a| + 1$.