Answer :

Subtract 4 from both sides, solve using quadratic formula
ax^2+bx+c
(-b(+or-) Square Root of b^2 - 4ac)/2a

9x^2+9x-4=0
-9(+or-)Square root of 9^2-4(9)(-4)/2(9)

Solve^
9x² + 9x = 4
9x² + 9x - 4 = 4 - 4
9x² + 9x - 4 = 0
x = -9 +/- √(9² - 4(9)(-4))
                2(9)
x = -9 +/- √(81 + 144)
                 18
x = -9 +/- √225
            18
x = -9 +/- 15
           18
x = -9 + 15    x = -9 - 15
          18                 18
x = 6             x = -24
     18                    18
x = 1/3            x = -1 1/3