5h(2h-3)+2h=21

Solution for 5h(2h-3)+2h=21 equation:

5h(2h-3)+2h=21

We move all terms to the left:

5h(2h-3)+2h-(21)=0

We add all the numbers together, and all the variables

2h+5h(2h-3)-21=0

We multiply parentheses

10h^2+2h-15h-21=0

We add all the numbers together, and all the variables

10h^2-13h-21=0

a = 10; b = -13; c = -21;
Δ = b2-4ac
Δ = -132-4·10·(-21)
Δ = 1009
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$h_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$h_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$h_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-13)-\sqrt{1009}}{2*10}=\frac{13-\sqrt{1009}}{20}
$
$h_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-13)+\sqrt{1009}}{2*10}=\frac{13+\sqrt{1009}}{20}
$