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Which of the following are solutions to the equation below? Check all that apply. 4x2 - 12x + 9 = 5​

User Charleh
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1 Answer

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14 votes

Explanation:

4x² - 12x + 9 = 5 → 4x² - 12x + 4 = 0 → x² - 3x + 1 = 0

∆ = b² - 4ac → ∆ = (-3)² -4(1)(1) = 9 - 4 = 5

x = (-(-3) ± √5)/2(1) = (3 ± √5)/2

x² - 3x + 1 = 0 → (x - 3/2)² - 9/4 + 1 = 0 → (x - 3/2)² = 5/4 → x - 3/2 = ±√5 / 2 → x = ½( 3 ± √5)

User Dimlucas
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