x^2+7x+12.25=12.2

Solution for x^2+7x+12.25=12.2 equation:

x^2+7x+12.25=12.2

We move all terms to the left:

x^2+7x+12.25-(12.2)=0

We add all the numbers together, and all the variables

x^2+7x+0.050000000000001=0

a = 1; b = 7; c = +0.050000000000001;
Δ = b2-4ac
Δ = 72-4·1·0.050000000000001
Δ = 48.8
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{-(7)-\sqrt{48.8}}{2*1}=\frac{-7-\sqrt{48.8}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+\sqrt{48.8}}{2*1}=\frac{-7+\sqrt{48.8}}{2}
$