2a2+9a-200=0

Solution for 2a2+9a-200=0 equation:

2a^2+9a-200=0

a = 2; b = 9; c = -200;
Δ = b2-4ac
Δ = 92-4·2·(-200)
Δ = 1681
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1681}=41$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(9)-41}{2*2}=\frac{-50}{4}
=-12+1/2
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(9)+41}{2*2}=\frac{32}{4}
=8
$