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Question
Solve the following quadratic equation using formula method only
x2 - 6x + 4 = 0
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Solution
x2 - 6x + 4 = 0
a = 1 ; b = - 6 ; c = 4
D = b2 - 4ac
= (-6)2 - 4(1)(4)
= 36 - 16
= 20
x = `(- "b" ± sqrt ("b"^2 - 4 "ac"))/(2a)`
x = `(6 +- sqrt 20)/2`
x = `(6 +2 sqrt 5)/2` , x = `(6 - 2 sqrt 5)/2`
x = `3 + sqrt 5` , x = `3 - sqrt 5`
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