8y^2-42y-88=0

Solution for 8y^2-42y-88=0 equation:

8y^2-42y-88=0

a = 8; b = -42; c = -88;
Δ = b2-4ac
Δ = -422-4·8·(-88)
Δ = 4580
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{4580}=\sqrt{4*1145}=\sqrt{4}*\sqrt{1145}=2\sqrt{1145}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-42)-2\sqrt{1145}}{2*8}=\frac{42-2\sqrt{1145}}{16}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-42)+2\sqrt{1145}}{2*8}=\frac{42+2\sqrt{1145}}{16}
$