(2x+10)(2x+15)=0

Solution for (2x+10)(2x+15)=0 equation:

(2x+10)(2x+15)=0

We multiply parentheses ..

(+4x^2+30x+20x+150)=0

We get rid of parentheses

4x^2+30x+20x+150=0

We add all the numbers together, and all the variables

4x^2+50x+150=0

a = 4; b = 50; c = +150;
Δ = b2-4ac
Δ = 502-4·4·150
Δ = 100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{100}=10$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(50)-10}{2*4}=\frac{-60}{8}
=-7+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(50)+10}{2*4}=\frac{-40}{8}
=-5
$