x^2+13.5x+2.5=0

Solution for x^2+13.5x+2.5=0 equation:

x^2+13.5x+2.5=0

a = 1; b = 13.5; c = +2.5;
Δ = b2-4ac
Δ = 13.52-4·1·2.5
Δ = 172.25
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{-(13.5)-\sqrt{172.25}}{2*1}=\frac{-13.5-\sqrt{172.25}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(13.5)+\sqrt{172.25}}{2*1}=\frac{-13.5+\sqrt{172.25}}{2}
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