(2x-15)(x+7)=0

Solution for (2x-15)(x+7)=0 equation:

(2x-15)(x+7)=0

We multiply parentheses ..

(+2x^2+14x-15x-105)=0

We get rid of parentheses

2x^2+14x-15x-105=0

We add all the numbers together, and all the variables

2x^2-1x-105=0

a = 2; b = -1; c = -105;
Δ = b2-4ac
Δ = -12-4·2·(-105)
Δ = 841
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{841}=29$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-29}{2*2}=\frac{-28}{4}
=-7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+29}{2*2}=\frac{30}{4}
=7+1/2
$