2x+7x+3x(x+1)=33

Solution for 2x+7x+3x(x+1)=33 equation:

2x+7x+3x(x+1)=33

We move all terms to the left:

2x+7x+3x(x+1)-(33)=0

We add all the numbers together, and all the variables

9x+3x(x+1)-33=0

We multiply parentheses

3x^2+9x+3x-33=0

We add all the numbers together, and all the variables

3x^2+12x-33=0

a = 3; b = 12; c = -33;
Δ = b2-4ac
Δ = 122-4·3·(-33)
Δ = 540
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:

$\sqrt{\Delta}=\sqrt{540}=\sqrt{36*15}=\sqrt{36}*\sqrt{15}=6\sqrt{15}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-6\sqrt{15}}{2*3}=\frac{-12-6\sqrt{15}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+6\sqrt{15}}{2*3}=\frac{-12+6\sqrt{15}}{6}
$