(8e+8)(9e-3)=90

Solution for (8e+8)(9e-3)=90 equation:

(8e+8)(9e-3)=90

We move all terms to the left:

(8e+8)(9e-3)-(90)=0

We multiply parentheses ..

(+72e^2-24e+72e-24)-90=0

We get rid of parentheses

72e^2-24e+72e-24-90=0

We add all the numbers together, and all the variables

72e^2+48e-114=0

a = 72; b = 48; c = -114;
Δ = b2-4ac
Δ = 482-4·72·(-114)
Δ = 35136
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$e_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$e_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{35136}=\sqrt{576*61}=\sqrt{576}*\sqrt{61}=24\sqrt{61}$
$e_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(48)-24\sqrt{61}}{2*72}=\frac{-48-24\sqrt{61}}{144}
$
$e_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(48)+24\sqrt{61}}{2*72}=\frac{-48+24\sqrt{61}}{144}
$