1890=w^2-3w

Solution for 1890=w^2-3w equation:

1890=w^2-3w

We move all terms to the left:

1890-(w^2-3w)=0

We get rid of parentheses

-w^2+3w+1890=0

We add all the numbers together, and all the variables

-1w^2+3w+1890=0

a = -1; b = 3; c = +1890;
Δ = b2-4ac
Δ = 32-4·(-1)·1890
Δ = 7569
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{7569}=87$
$w_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-87}{2*-1}=\frac{-90}{-2}
=+45
$
$w_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+87}{2*-1}=\frac{84}{-2}
=-42
$