(X+5)(2x+7)=0

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

(X+5)(2X+7)=0

We multiply parentheses ..

(+2X^2+7X+10X+35)=0

We get rid of parentheses

2X^2+7X+10X+35=0

We add all the numbers together, and all the variables

2X^2+17X+35=0

a = 2; b = 17; c = +35;
Δ = b2-4ac
Δ = 172-4·2·35
Δ = 9
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9}=3$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(17)-3}{2*2}=\frac{-20}{4}
=-5
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(17)+3}{2*2}=\frac{-14}{4}
=-3+1/2
$