2n^2+15n+13=0

Solution for 2n^2+15n+13=0 equation:

2n^2+15n+13=0

a = 2; b = 15; c = +13;
Δ = b2-4ac
Δ = 152-4·2·13
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(15)-11}{2*2}=\frac{-26}{4}
=-6+1/2
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+11}{2*2}=\frac{-4}{4}
=-1
$