Question

If (x + a) is a factor of `(2x^2 + 2ax + 5x + 10)`, then find the value of a. 

 

Answer 1

Given: (x + a) is a factor of `2x^2 + 2ax + 5x + 10`
We have 

x + a = 0
⇒ x = –a 

Since, (x + a) is a factor of `2x^2 + 2ax + 5x + 10`
Hence, It will satisfy the above polynomial
∴ `2(–a)^2 + 2a(–a) + 5(–a) + 10 = 0`
`⇒ –5a + 10 = 0`
`⇒ a = 2`