5x(2x+6)=-26+6

Solution for 5x(2x+6)=-26+6 equation:

5x(2x+6)=-26+6

We move all terms to the left:

5x(2x+6)-(-26+6)=0

We add all the numbers together, and all the variables

5x(2x+6)-(-20)=0

We add all the numbers together, and all the variables

5x(2x+6)+20=0

We multiply parentheses

10x^2+30x+20=0

a = 10; b = 30; c = +20;
Δ = b2-4ac
Δ = 302-4·10·20
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{-(30)-10}{2*10}=\frac{-40}{20}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+10}{2*10}=\frac{-20}{20}
=-1
$