x+4x(7x-15)=180

Solution for x+4x(7x-15)=180 equation:

x+4x(7x-15)=180

We move all terms to the left:

x+4x(7x-15)-(180)=0

We multiply parentheses

28x^2+x-60x-180=0

We add all the numbers together, and all the variables

28x^2-59x-180=0

a = 28; b = -59; c = -180;
Δ = b2-4ac
Δ = -592-4·28·(-180)
Δ = 23641
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-59)-\sqrt{23641}}{2*28}=\frac{59-\sqrt{23641}}{56}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-59)+\sqrt{23641}}{2*28}=\frac{59+\sqrt{23641}}{56}
$