Question

Please help me solve x^3+12x^2+47x-60=0.

Answer 1

Note that this is a 3rd order polynomial, so the quadratic equation does not apply here. I would suggest you either try to factor, or try to identify possible roots by looking at all factors of -60.

Answer 2

Factors of -60 include plus or minus 1, p or m 2, p or m 3, p or m 4, and so on.
Do you have any experience with synthetic division? If so, use it here to determine whether or not 4 is a root o the given cubic equation.

Answer 3

Try to see that x=1 is a root.

Answer 4

It is clear that
1+12+47-60=60-60=0

Answer 5

Divide your polynomial by x-1

Answer 6

You get
\[
\frac{x^3+12 x^2+47 x-60}{x-1}=x^2+13 x+60
\]

Answer 7

Use the quadratic formula to finish