(3x+15)(x+10)=103

Solution for (3x+15)(x+10)=103 equation:

(3x+15)(x+10)=103

We move all terms to the left:

(3x+15)(x+10)-(103)=0

We multiply parentheses ..

(+3x^2+30x+15x+150)-103=0

We get rid of parentheses

3x^2+30x+15x+150-103=0

We add all the numbers together, and all the variables

3x^2+45x+47=0

a = 3; b = 45; c = +47;
Δ = b2-4ac
Δ = 452-4·3·47
Δ = 1461
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{-(45)-\sqrt{1461}}{2*3}=\frac{-45-\sqrt{1461}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(45)+\sqrt{1461}}{2*3}=\frac{-45+\sqrt{1461}}{6}
$