6h^2-25h+21=0

Solution for 6h^2-25h+21=0 equation:

6h^2-25h+21=0

a = 6; b = -25; c = +21;
Δ = b2-4ac
Δ = -252-4·6·21
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$h_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$h_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$h_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-25)-11}{2*6}=\frac{14}{12}
=1+1/6
$
$h_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-25)+11}{2*6}=\frac{36}{12}
=3
$