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An equation $x^{2} - (k + 2) x + (2 k) = 0$ is examined. For which value of $k$ are the roots real and equal?

Class 10Discriminant and Nature of RootsAlgebra — Quadratics

A3
B1
C2
D4

Step-by-Step Solution

D = 0 : (k + 2)^{2} - 8 k = 0

, so

k^{2} + 4 k + 4 - 8 k = 0

, i.e.

k^{2} - 4 k + 4 = 0, (k - 2)^{2} = 0

, giving

k = 2

.

Answer: C) 2

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