-3x(x+5)+2x=-15-x

Solution for -3x(x+5)+2x=-15-x equation:

-3x(x+5)+2x=-15-x

We move all terms to the left:

-3x(x+5)+2x-(-15-x)=0

We add all the numbers together, and all the variables

-3x(x+5)+2x-(-1x-15)=0

We add all the numbers together, and all the variables

2x-3x(x+5)-(-1x-15)=0

We multiply parentheses

-3x^2+2x-15x-(-1x-15)=0

We get rid of parentheses

-3x^2+2x-15x+1x+15=0

We add all the numbers together, and all the variables

-3x^2-12x+15=0

a = -3; b = -12; c = +15;
Δ = b2-4ac
Δ = -122-4·(-3)·15
Δ = 324
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{324}=18$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-18}{2*-3}=\frac{-6}{-6}
=1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+18}{2*-3}=\frac{30}{-6}
=-5
$