x^2+2.8^2=3.5^2

Solution for x^2+2.8^2=3.5^2 equation:

x^2+2.8^2=3.5^2

We move all terms to the left:

x^2+2.8^2-(3.5^2)=0

We add all the numbers together, and all the variables

x^2-4.41=0

a = 1; b = 0; c = -4.41;
Δ = b2-4ac
Δ = 02-4·1·(-4.41)
Δ = 17.64
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{17.64}}{2*1}=\frac{0-\sqrt{17.64}}{2}
=-\frac{\sqrt{}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{17.64}}{2*1}=\frac{0+\sqrt{17.64}}{2}
=\frac{\sqrt{}}{2}
$