Q. 23 C5.0( 2 Votes )

# If x = 2 is a root of the equation x^{2} — 4x + a = 0, then a =

A. —2

B. 2

C. —4

D. 4

Answer :

∵ 2 is a root

⇒ (2)^{2} – 4(2) + a = 0

⇒ 4 – 8 + a = 0

⇒ a = 4

(A) doesn’t match the solution.

(B) doesn’t match the solution.

(C) doesn’t match the solution.

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