20. If (x + a) is a factor of the polynomial 2x² + 2ax + 5x + 10, fin

1.	20. If (x + a) is a factor of the polynomial 2x² + 2ax + 5x + 10, find the valueof a.[CBSE 2009)
Answer» x+a is a factor of 2x²+2ax+5x+10therefore f(-a)=0;substituting values,2(-a)²+2(a)(-a)+5(-a)+10=02a²-2a²-5a+10=0-5a+10=0therefore a=2 -5a = -10 a = 2 x+a=0x=-ap(-a)=0-5a+10=0-5a=-10a=10/5a=2 the value of a is 2 is the correct answer of the given question

20. If (x + a) is a factor of the polynomial 2x² + 2ax + 5x + 10, find the valueof a.[CBSE 2009)

Answer»

x+a is a factor of 2x²+2ax+5x+10therefore f(-a)=0;substituting values,2(-a)²+2(a)(-a)+5(-a)+10=02a²-2a²-5a+10=0-5a+10=0therefore a=2

-5a = -10 a = 2

x+a=0x=-ap(-a)=0-5a+10=0-5a=-10a=10/5a=2

the value of a is 2 is the correct answer of the given question