660x(3/10)=30

Solution for 660x(3/10)=30 equation:

660x(3/10)=30

We move all terms to the left:

660x(3/10)-(30)=0

We add all the numbers together, and all the variables

660x(+3/10)-30=0

We multiply parentheses

1980x^2-30=0

a = 1980; b = 0; c = -30;
Δ = b2-4ac
Δ = 02-4·1980·(-30)
Δ = 237600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{237600}=\sqrt{3600*66}=\sqrt{3600}*\sqrt{66}=60\sqrt{66}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-60\sqrt{66}}{2*1980}=\frac{0-60\sqrt{66}}{3960}
=-\frac{60\sqrt{66}}{3960}
=-\frac{\sqrt{66}}{66}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+60\sqrt{66}}{2*1980}=\frac{0+60\sqrt{66}}{3960}
=\frac{60\sqrt{66}}{3960}
=\frac{\sqrt{66}}{66}
$