2z^2-17z+8=0

Solution for 2z^2-17z+8=0 equation:

2z^2-17z+8=0

a = 2; b = -17; c = +8;
Δ = b2-4ac
Δ = -172-4·2·8
Δ = 225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{225}=15$
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-17)-15}{2*2}=\frac{2}{4}
=1/2
$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-17)+15}{2*2}=\frac{32}{4}
=8
$