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प्रश्न
Solve the following quadratic equation using formula method only
25x2 + 30x + 7 = 0
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उत्तर
25x2 + 30x + 7 = 0
a = 25 ; b = 30 ; c = 7
D = b2 - 4ac
= (30)2 - 4(25)(7)
= 900 - 700
= 200
x = `(- "b" ± sqrt ("b"^2 - 4 "ac"))/(2a)`
x = `(-30 +- sqrt 200)/50`
x = `(-30 + 10 sqrt 2)/50` x = `(-30 - 10 sqrt 2)/50`
x = `(- 3 + sqrt 2)/5` , x = `(- 3 - sqrt 2)/5`
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