0=28x^2+27x-10

Solution for 0=28x^2+27x-10 equation:

0=28x^2+27x-10

We move all terms to the left:

0-(28x^2+27x-10)=0

We add all the numbers together, and all the variables

-(28x^2+27x-10)=0

We get rid of parentheses

-28x^2-27x+10=0

a = -28; b = -27; c = +10;
Δ = b2-4ac
Δ = -272-4·(-28)·10
Δ = 1849
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1849}=43$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-27)-43}{2*-28}=\frac{-16}{-56}
=2/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-27)+43}{2*-28}=\frac{70}{-56}
=-1+1/4
$