# Solve the quadratic by using the quadratic formula x^2 = 7x + 9

Question
Solve the quadratic by using the quadratic formula x^2 = 7x + 9

2021-02-01
x^2 - 7x - 9 a=1, b=-7, c=-9 Quadratic ormula: x=(-b+-sqrt(b^2-4ac))/(2a) =(-(-7)+-sqrt((-7)^2-4(1)(-9)))/(2(1)) =(7+-sqrt(49+36))/2 =(7+-sqrt85)/2 x=(7+sqrt85)/2, (7-sqrt85)/2

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