(x+6)(2x+5)=

Solution for (x+6)(2x+5)= equation:

(x+6)(2x+5)=

We move all terms to the left:

(x+6)(2x+5)-()=0

We add all the numbers together, and all the variables

(x+6)(2x+5)=0

We multiply parentheses ..

(+2x^2+5x+12x+30)=0

We get rid of parentheses

2x^2+5x+12x+30=0

We add all the numbers together, and all the variables

2x^2+17x+30=0

a = 2; b = 17; c = +30;
Δ = b2-4ac
Δ = 172-4·2·30
Δ = 49
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{49}=7$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(17)-7}{2*2}=\frac{-24}{4}
=-6
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(17)+7}{2*2}=\frac{-10}{4}
=-2+1/2
$