(2x)(4x-30)=180

Solution for (2x)(4x-30)=180 equation:

(2x)(4x-30)=180

We move all terms to the left:

(2x)(4x-30)-(180)=0

We multiply parentheses

8x^2-60x-180=0

a = 8; b = -60; c = -180;
Δ = b2-4ac
Δ = -602-4·8·(-180)
Δ = 9360
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:

$\sqrt{\Delta}=\sqrt{9360}=\sqrt{144*65}=\sqrt{144}*\sqrt{65}=12\sqrt{65}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-60)-12\sqrt{65}}{2*8}=\frac{60-12\sqrt{65}}{16}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-60)+12\sqrt{65}}{2*8}=\frac{60+12\sqrt{65}}{16}
$