3x(x-2)+5=60

Solution for 3x(x-2)+5=60 equation:

3x(x-2)+5=60

We move all terms to the left:

3x(x-2)+5-(60)=0

We add all the numbers together, and all the variables

3x(x-2)-55=0

We multiply parentheses

3x^2-6x-55=0

a = 3; b = -6; c = -55;
Δ = b2-4ac
Δ = -62-4·3·(-55)
Δ = 696
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:

$\sqrt{\Delta}=\sqrt{696}=\sqrt{4*174}=\sqrt{4}*\sqrt{174}=2\sqrt{174}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-2\sqrt{174}}{2*3}=\frac{6-2\sqrt{174}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+2\sqrt{174}}{2*3}=\frac{6+2\sqrt{174}}{6}
$