(3x+8)(x+10)=0

Solution for (3x+8)(x+10)=0 equation:

(3x+8)(x+10)=0

We multiply parentheses ..

(+3x^2+30x+8x+80)=0

We get rid of parentheses

3x^2+30x+8x+80=0

We add all the numbers together, and all the variables

3x^2+38x+80=0

a = 3; b = 38; c = +80;
Δ = b2-4ac
Δ = 382-4·3·80
Δ = 484
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{484}=22$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(38)-22}{2*3}=\frac{-60}{6}
=-10
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(38)+22}{2*3}=\frac{-16}{6}
=-2+2/3
$