(10-4z)z=4

Solution for (10-4z)z=4 equation:

(10-4z)z=4

We move all terms to the left:

(10-4z)z-(4)=0

We add all the numbers together, and all the variables

(-4z+10)z-4=0

We multiply parentheses

-4z^2+10z-4=0

a = -4; b = 10; c = -4;
Δ = b2-4ac
Δ = 102-4·(-4)·(-4)
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-6}{2*-4}=\frac{-16}{-8}
=+2
$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+6}{2*-4}=\frac{-4}{-8}
=1/2
$