5c*8c=45c

Solution for 5c*8c=45c equation:

5c*8c=45c

We move all terms to the left:

5c*8c-(45c)=0

We add all the numbers together, and all the variables

-45c+5c*8c=0

Wy multiply elements

40c^2-45c=0

a = 40; b = -45; c = 0;
Δ = b2-4ac
Δ = -452-4·40·0
Δ = 2025
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2025}=45$
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-45)-45}{2*40}=\frac{0}{80}
=0
$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-45)+45}{2*40}=\frac{90}{80}
=1+1/8
$