40u^2+59u-8=0

Solution for 40u^2+59u-8=0 equation:

40u^2+59u-8=0

a = 40; b = 59; c = -8;
Δ = b2-4ac
Δ = 592-4·40·(-8)
Δ = 4761
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4761}=69$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(59)-69}{2*40}=\frac{-128}{80}
=-1+3/5
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(59)+69}{2*40}=\frac{10}{80}
=1/8
$