10w^2-21w+8=0

Solution for 10w^2-21w+8=0 equation:

10w^2-21w+8=0

a = 10; b = -21; c = +8;
Δ = b2-4ac
Δ = -212-4·10·8
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-21)-11}{2*10}=\frac{10}{20}
=1/2
$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-21)+11}{2*10}=\frac{32}{20}
=1+3/5
$