(2x+10)(7x-5)=0

Solution for (2x+10)(7x-5)=0 equation:

(2x+10)(7x-5)=0

We multiply parentheses ..

(+14x^2-10x+70x-50)=0

We get rid of parentheses

14x^2-10x+70x-50=0

We add all the numbers together, and all the variables

14x^2+60x-50=0

a = 14; b = 60; c = -50;
Δ = b2-4ac
Δ = 602-4·14·(-50)
Δ = 6400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{6400}=80$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(60)-80}{2*14}=\frac{-140}{28}
=-5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(60)+80}{2*14}=\frac{20}{28}
=5/7
$