10x2+89x=9

Solution for 10x2+89x=9 equation:

10x^2+89x=9

We move all terms to the left:

10x^2+89x-(9)=0

a = 10; b = 89; c = -9;
Δ = b2-4ac
Δ = 892-4·10·(-9)
Δ = 8281
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{8281}=91$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(89)-91}{2*10}=\frac{-180}{20}
=-9
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(89)+91}{2*10}=\frac{2}{20}
=1/10
$