Q. 23 G5.0( 2 Votes )

# If one of the roots of kx^{2} — 7x + 3 = 0 is 3, then k =

A. —2

B. 3

C. —3

D. 2

Answer :

∵ 3 is a root

⇒ k(3)^{2} – 7(3) + 3 = 0

⇒ 9k – 21 + 3 = 0

⇒ 9k = 18

⇒ k = 2

(A) doesn’t match the solution.

(B) doesn’t match the solution.

(C) doesn’t match the solution.

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