15b^2-115b+70=0

Solution for 15b^2-115b+70=0 equation:

15b^2-115b+70=0

a = 15; b = -115; c = +70;
Δ = b2-4ac
Δ = -1152-4·15·70
Δ = 9025
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9025}=95$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-115)-95}{2*15}=\frac{20}{30}
=2/3
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-115)+95}{2*15}=\frac{210}{30}
=7
$