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Find the values of k for which the followingequation has equal roots(k-12) x2 + 2 (k - 12) x + 2 = 0. |
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Answer» (k - 12)x² + 2(k - 12)x + 2 = 0a = k - 12b = 2(k - 12) = 2k - 24c = 2 To have equal roots, the discriminant must equal to 0D = 0b² - 4ac = 0(2k - 24)² - 4 . (k - 12) . 2 = 04k² - 96k + 576 - 8k + 96 = 04k² - 104k + 672 = 0 (divide by 4 for both sides of equation)k² - 26k + 168 = 0k² - 12k - 14k + 168 = 0k(k - 12) - 14(k - 12) = 0(k - 12)(k - 14) = 0k = 12 (not acceptable) or k = 14 (acceptable) not acceptable because if we put K for 12 the it will be 0x^2 not possible so we take 14 k= 14 is the correct answer of the given question |
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