## anonymous one year ago Identify the factors of x2 - 8x - 20. (x + 4)(x - 5) (x + 5)(x - 4) (x - 10)(x + 2) (x - 2)(x + 10)

1. Nnesha

4+ ways to factor quadratic equation leading coefficient is one so easy way to factor out is by using *AC method or headphone method whatever you wanna call it :D so find two number if you multiply them you should get product of AC and if you add or subtract them you should get middle term

2. anonymous

what?

3. Nnesha

ac and middle terms are $\huge\rm Ax^2+Bx+C=0$ where a= leading coefficient b=middle term c=constant term

4. Nnesha

so in this equation x^2-8x-20 a=1 c=-20 b=-8 so find two number if you mtuliply them you should get -20 and if you add or subtract them you should get -8

5. Nnesha

multiply**

6. anonymous

10 and 2???

7. Nnesha

one of them should be negative bec when you multiply them you should get -20

8. anonymous

oh i mean -10 and 2

9. Nnesha

yep right !

10. Nnesha

11. anonymous

c?

12. Nnesha

yep

13. anonymous

yay!!!

14. Nnesha

YAY! :=)