(4u-1)(4-u)=0

Solution for (4u-1)(4-u)=0 equation:

(4u-1)(4-u)=0

We add all the numbers together, and all the variables

(4u-1)(-1u+4)=0

We multiply parentheses ..

(-4u^2+16u+u-4)=0

We get rid of parentheses

-4u^2+16u+u-4=0

We add all the numbers together, and all the variables

-4u^2+17u-4=0

a = -4; b = 17; c = -4;
Δ = b2-4ac
Δ = 172-4·(-4)·(-4)
Δ = 225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{225}=15$
$u_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(17)-15}{2*-4}=\frac{-32}{-8}
=+4
$
$u_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(17)+15}{2*-4}=\frac{-2}{-8}
=1/4
$