Question

What is the complete factorization of x^2+4x-45?​

Answer 1

Answer:(x-5)(x+9)

Step-by-step explanation:

You want two numbers that can give you -45 in multiplication and two numbers that can add to 4 and that is -5 and 9.

Answer 2

Answer:  (x - 5)(x + 9)

If you have to solve, x=5 or x= -9

Step-by-step explanation: You need two numbers that multiply to be 45.

(could be 3 × 15 or 5 × 9) . The difference between the two factors needs to be 4, the coefficient of the middle term.

9 - 5 =4, so use those.  -45 has a negative sign, so one of the factors must be + and the other -  Since the 4 has the + sign, the larger factor has to be + so the difference will be positive.

So (x -5)(x + 9) are your factors. You can FOIL to be sure

x × x += x² . x × 9 = 9x .  -5 ×  x = -5x . -5 × 9 = -45 .

Combine the x terms: 9x -5x = +4x