10a^2-43a-66=0

Solution for 10a^2-43a-66=0 equation:

10a^2-43a-66=0

a = 10; b = -43; c = -66;
Δ = b2-4ac
Δ = -432-4·10·(-66)
Δ = 4489
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4489}=67$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-43)-67}{2*10}=\frac{-24}{20}
=-1+1/5
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-43)+67}{2*10}=\frac{110}{20}
=5+1/2
$