x^2+2.5-9=0

Solution for x^2+2.5-9=0 equation:

x^2+2.5-9=0

We add all the numbers together, and all the variables

x^2-6.5=0

a = 1; b = 0; c = -6.5;
Δ = b2-4ac
Δ = 02-4·1·(-6.5)
Δ = 26
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{26}}{2*1}=\frac{0-\sqrt{26}}{2}
=-\frac{\sqrt{}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{26}}{2*1}=\frac{0+\sqrt{26}}{2}
=\frac{\sqrt{}}{2}
$