Respuesta :

Answer:

10x2 + 30x - 40

Step-by-step explanation:

If the two roots are -2 and 4 then the factors shall be;

5(x+2)(x-4)

5 is the leading coefficient.

FOIL:

f(x) = 5(x2+4x+2x-8) =

f(x) = 5(x2+6x-8) =

f(x) = 10x2 + 30x - 40

Answer:5x^2-10x-40=0

Step-by-step explanation:

x=-2 or x=4

x+2=0 or x-4=0

(x+2)(x-4)=0

x^2-4x+2x-8=0

x^2-2x-8=0

Multiply the equation by 5

5x^2-10x-40=0