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Question
Solve the following quadratic equation using formula method only
`"x"^2 + 1/2 "x" = 3`
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Solution
`"x"^2 + 1/2 "x" = 3`
2x2 + x = 6
2x2 + x - 6 = 0
a = 2 ; b = 1 ; c = -6
D = b2 - 4ac
= (1)2 - 4(2)(-6)
= 1 + 48
= 49
x = `(- "b" ± sqrt ("b"^2 - 4 "ac"))/(2a)`
x = `(-1 +- sqrt 49)/4`
x = `(- 1 + 7)/4` , x = `(- 1 - 7)/4`
x = `6/4` , x = `-8/4`
x = `3/2` , x = - 2
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