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Use the quadratic formula to solve 9x2 + 6x – 17 = 0

2 Answers

5 votes

Answer: x= -1 + 3 sq root 2 /3

Explanation:

the plus has a Line under it

User Rajitha Perera
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The standard form of a quadratic equation is :

ax² + bx + c = 0

And the quadratic formula is:


x=(-b\pm√(b^2-4ac))/(2a).

So, first step is to compare the given equation with the above equation to get the value of a, b and c.

So, a = 9, b = 6 and c = - 17.

Next step is to plug in these values in the above formula. Therefore,


x=(-6\pm√(6^2-4*(9)*(-17)))/(2*9)


=(-6\pm√(36+612))/(18)


=(-6\pm√(648))/(18)


=(-6\pm√(324*2))/(18)


=(-6\pm√(324)*√(2))/(18)


=(-6\pm18*√(2))/(18)


=-(6)/(18) \pm(18√(2))/(18)


=-(1)/(3) \pm√(2).

So, x =
-(1)/(3) \pm√(2)

User Arsenal
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