Question

How do you solve `9x^2+12x+4=0` using the quadratic formula?

Answer 1

`x = (-2/3)(1 +- sqrt2)`

Explanation:

Use the improved quadratic formula:
`D = d^2 = b^2 - 4ac = 144 + 144 = 288` --> `d = +-sqrt(144*2) =`
`= +- 12sqrt2`
There are 2 real roots:
`x = -b/(2a) +- d/(2a) = -12/18 +- 12sqrt2/18 =`
`- 2/3 +- (2/3)sqrt2 = (-2/3)(1 +- sqrt2)`