-0.33(9x+42)5x=-70

Solution for -0.33(9x+42)5x=-70 equation:

-0.33(9x+42)5x=-70

We move all terms to the left:

-0.33(9x+42)5x-(-70)=0

We add all the numbers together, and all the variables

-0.33(9x+42)5x+70=0

We multiply parentheses

-9x^2-42x+70=0

a = -9; b = -42; c = +70;
Δ = b2-4ac
Δ = -422-4·(-9)·70
Δ = 4284
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:

$\sqrt{\Delta}=\sqrt{4284}=\sqrt{36*119}=\sqrt{36}*\sqrt{119}=6\sqrt{119}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-42)-6\sqrt{119}}{2*-9}=\frac{42-6\sqrt{119}}{-18}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-42)+6\sqrt{119}}{2*-9}=\frac{42+6\sqrt{119}}{-18}
$