How do you solve the quadratic using the quadratic formula given $9x^2-11=6x$ ?

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Answer 1 · 2016-10-27T11:49:43

We put our equation into standard form, then use the quadratic equation to find

$x=(1 +- 2sqrt(3))/3 ~= 1.49, -0.821$

To use the quadratic formula, we must first put our equation into the standard form:

$ax^2+bx+c=0$

We can do this by subtracting $6x$ from both sides of our equation yielding:

$9x^2-6x-11=0$

This allows us to match up the values

$a=9, b=-6" "$ and $" "c=-11$

Then we use the quadratic formula:

$x = (-b +- sqrt(b^2-4ac))/(2a)=(6 +- sqrt(36-4*9*(-11)))/18$

$x=(6 +- sqrt(432))/18 = (1 +- 2sqrt(3))/3$

$x~= 1.49, -0.821$

How do you solve the quadratic using the quadratic formula given 9x^2-11=6x9x^2-11=6x?