8(2k+5)(k+5)=

Solution for 8(2k+5)(k+5)= equation:

8(2k+5)(k+5)=

We move all terms to the left:

8(2k+5)(k+5)-()=0

We add all the numbers together, and all the variables

8(2k+5)(k+5)=0

We multiply parentheses ..

8(+2k^2+10k+5k+25)=0

We multiply parentheses

16k^2+80k+40k+200=0

We add all the numbers together, and all the variables

16k^2+120k+200=0

a = 16; b = 120; c = +200;
Δ = b2-4ac
Δ = 1202-4·16·200
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(120)-40}{2*16}=\frac{-160}{32}
=-5
$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(120)+40}{2*16}=\frac{-80}{32}
=-2+1/2
$