81x^2-289=0

Solution for 81x^2-289=0 equation:

81x^2-289=0

a = 81; b = 0; c = -289;
Δ = b2-4ac
Δ = 02-4·81·(-289)
Δ = 93636
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{93636}=306$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-306}{2*81}=\frac{-306}{162}
=-1+8/9
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+306}{2*81}=\frac{306}{162}
=1+8/9
$