(x-5)+1.4+x+x(x+35)=360

Solution for (x-5)+1.4+x+x(x+35)=360 equation:

(x-5)+1.4+x+x(x+35)=360

We move all terms to the left:

(x-5)+1.4+x+x(x+35)-(360)=0

We add all the numbers together, and all the variables

x+(x-5)+x(x+35)-358.6=0

We multiply parentheses

x^2+x+(x-5)+35x-358.6=0

We get rid of parentheses

x^2+x+x+35x-5-358.6=0

We add all the numbers together, and all the variables

x^2+37x-363.6=0

a = 1; b = 37; c = -363.6;
Δ = b2-4ac
Δ = 372-4·1·(-363.6)
Δ = 2823.4
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{-(37)-\sqrt{2823.4}}{2*1}=\frac{-37-\sqrt{2823.4}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(37)+\sqrt{2823.4}}{2*1}=\frac{-37+\sqrt{2823.4}}{2}
$