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One root of $x^{2} - 12 x + k = 0$ is twice the other root.
What is the value of $k$ ?

Class 10Sum and Product of RootsAlgebra — Quadratics

A32
B24
C16
D36

Step-by-Step Solution

Let roots be

r

and

2 r

. Sum

3 r = 12

, so

r = 4

. Roots are 4 and 8; product

k = 4 \times 8 = 32

.

Answer: A) 32

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