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Solve the equation using the quadratic formula. 3x^2+7x-20=0

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11 votes

Answer:

Explanation:

a = co-efficient of x² = 3

b = co-efficient of x = 7

c = constant = -20

Determinant = D = b² -4ac

= 7² - 4*3*(-20)

= 49 + 240

= 289


x =(-b + √(D))/(2a) ; \ x =(-b- √(D))/(2a)\\\\\\x=(-7+√(289))/(2*3) ; \ x=(-3-√(289))/(2*30)\\\\\\x=(-7+17)/(6) ; \ x=(-7-17)/(6)\\\\x=(10)/(6); \ x=(-24)/(6)\\

x = 5/3 ; x = -4

User Jesse Carter
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