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Find the Values Of K For Which the Roots Are Real and Equal in Each of the Following Equation: 2kx2 - 40x + 25 = 0

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प्रश्न

Find the values of k for which the roots are real and equal in each of the following equation:

2kx2 - 40x + 25 = 0

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उत्तर

The given quadric equation is 2kx2 - 40x + 25 = 0, and roots are real and equal

Then find the value of k.

Here, a = 2k, b = -40 and c = 25

As we know that D = b2 - 4ac

Putting the value of a = 2k, b = -40 and c = 25

= (-40)2 - 4 x (2k) x (25)

=1600 - 200k

The given equation will have real and equal roots, if D = 0

Thus,

1600 - 200k = 0

200k = 1600

k = 1600/200

k = 8

Therefore, the value of k = 8.

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अध्याय 4: Quadratic Equations - Exercise 4.6 [पृष्ठ ४१]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 10
अध्याय 4 Quadratic Equations
Exercise 4.6 | Q 2.05 | पृष्ठ ४१

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