x2-5x+6.25=4

Solution for x2-5x+6.25=4 equation:

x2-5x+6.25=4

We move all terms to the left:

x2-5x+6.25-(4)=0

We add all the numbers together, and all the variables

x^2-5x+2.25=0

a = 1; b = -5; c = +2.25;
Δ = b2-4ac
Δ = -52-4·1·2.25
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-5)-4}{2*1}=\frac{1}{2}
=1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5)+4}{2*1}=\frac{9}{2}
=4+1/2
$