Question

If (x + a) is a factor 2x^2 + 2ax + 5x + 10, find a.

Answer 1

Step-by-step explanation:

p(x)=2x²+2ax+5x+10

g(x)=x+a

=>x+a=0

=>x=-a

p(-a)=2(-a)²+2a(-a)+5(-a)+10

=>2a²-2a²-5a+10=0

=>10-5a=0

=>5a=10

=>a=2