Question

If (x+2)and (x-1) are factors of the polynomial 10x^2+px+q then pq is

Answer 1

Answer:

x+2=0

x=-2

10(-2)^2+p(-2)+q=0

40-2p+q=0

2p+q=-40

-(2p-q)=-40

2p-q =40 _____(1)

x-1=0

x=1

10(1)+p(1)+q=0

10+p+q=0

p+q=-10______(2)

2×(2)-(1)

q=-20

p=30

pq= 30×-20=-600