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प्रश्न
If one root of the quadratic, x2 - 7x + k = 0 is 4. then find the value of k.
उत्तर
x2 - 7x + k = 0 ( Given )
∵ 4 is the root of this quadratic equation.
∴ 4 will satisfy this equation.
∴ Put x = a
42 - 7( 4) + k = 0
∴ 16 - 28 + k = 0
-12 + k = 0
∴ k = 12
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