2c^2+c-105=0

Solution for 2c^2+c-105=0 equation:

2c^2+c-105=0

a = 2; b = 1; c = -105;
Δ = b2-4ac
Δ = 12-4·2·(-105)
Δ = 841
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{841}=29$
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-29}{2*2}=\frac{-30}{4}
=-7+1/2
$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+29}{2*2}=\frac{28}{4}
=7
$