How do you factor 3x^3+x^2-75x-25?

1 Answer
Mar 29, 2017

This actually requires factoring by grouping. Let's group the function like this: (3x^3+x^2)-(75x+25). We then factor the two groups to get x^2(3x+1)-25(3x+1). The common factor between the two groups is (3x+1), which we factor out to get (3x+1)(x^2-25).

Now, we notice that x^2-25=(x+5)(x-5) (using the difference between squares identity).

Thus, our final answer is (3x+1)(x+5)(x-5)