Question

Given the trinomial x^2+bx+c where both the first and second signs are positive, the signs of the factors will be: A. both negative , B. one positive and one negative, C. both positive, D. cannot determine

Answer 1

The answer here is C. The sign of the factors are both positive. We can use the FOIL method as reference in determining the sign of the factors. The 3rd term C is positive; therefore our only option is either both negative or both positive. Looking the middle term, which is positive, we know that the middle term is the sum of the outer and inner in FOIL method, which means, signs of the factors must be both positive