Could someone please explain the steps in finding all the zeroes of the equation

Question

x^4-6x^2-7x-6=0

Have no idea

Answer 1

you know the rational roots, if any, are among ±1 ±2 ±3 ±6

so, try some and fond that -2 and 3 are roots.

dividing those out you find you have

(x+2)(x-3)(x^2 + x + 1)

find the other two roots using the quadratic formula