Q20 of 113 Page 50

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

Since, x + a is a factor of 2x2 + 2ax + 5x + 10

∴ x + a = 0


x = -a


Put x = -a in 2x2 + 2ax + 5x + 10 = 0


2(-a)2 + 2a(-a) + 5(-a) + 10 = 0


2a2 – 2a2 – 5a + 10 = 0


-5a = - 10


a = 2


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