9x^2-6.25=0

Solution for 9x^2-6.25=0 equation:

9x^2-6.25=0

a = 9; b = 0; c = -6.25;
Δ = b2-4ac
Δ = 02-4·9·(-6.25)
Δ = 225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{225}=15$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-15}{2*9}=\frac{-15}{18}
=-5/6
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+15}{2*9}=\frac{15}{18}
=5/6
$