Question

If (x+a) is a factor of 2xsquare+2ax+ 5x+10 ,find a ( class 9 lesson 2 polynomials)

Answer 1

If x+a is the factor then, x+a= 0........x= -a.................. The p(x)= 2x^2 + 2ax + 5x + 10.................... Pu the value of x...... p( -a )= 2(-a)^2+2a(-a)+5( -a) +10= 0................. p(-a) = 2a^2-2a^2-5a+10= 0.................. ( 2a^2 and -2a^2 gets cancelled).......... -5a+10= 0, a= -10/-5= 2.................... So, a= 2....