2u^2+17u-9=0

Solution for 2u^2+17u-9=0 equation:

2u^2+17u-9=0

a = 2; b = 17; c = -9;
Δ = b2-4ac
Δ = 172-4·2·(-9)
Δ = 361
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{361}=19$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(17)-19}{2*2}=\frac{-36}{4}
=-9
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(17)+19}{2*2}=\frac{2}{4}
=1/2
$