Question

find all the common zeros of the polynomials: x3+5x2-9x-45 and x3+8x2+15x​

Answer 1

Answer:

Let P(x) = x3 + 5x2 - 9x - 45 and Q(x) = x3 + 8x2 + 15x.

Let P(x) = x3 + 5x2 - 9x - 45 = x2(x + 5) - 9 (x+5)

= (x+5) (x2 - 9)

= (x+5) (x+3) (x-3)

Q(x) = x3 + 8x2 + 15x = x(x2 + 8x + 15)

= x (x+5) (x+3) ∴ The common zeroes of the polynomials are (x+5) and (x+3).

polynomials are (x+5) and (x+3).

Answer 2

Answer:

x3+5x2-9x-45 and x3+8x2+15x

Step-by-step explanation:

First polynomial Second polynomial

x3+5x2-9x-45=0 x3+8x2+15x

x2(x+5)-9(x+5)=0 x(x2+8x+15)

(x+5)(x2-9)=0 x(x+3)(x+5)

x+5=0 x2-9=0 x=0,-3,-5

x=-5. x2=9

x=3