(5x-2)(x=8)

Solution for (5x-2)(x=8) equation:

(5x-2)(x=8)

We move all terms to the left:

(5x-2)(x-(8))=0

We multiply parentheses ..

(+5x^2-40x-2x+16)=0

We get rid of parentheses

5x^2-40x-2x+16=0

We add all the numbers together, and all the variables

5x^2-42x+16=0

a = 5; b = -42; c = +16;
Δ = b2-4ac
Δ = -422-4·5·16
Δ = 1444
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1444}=38$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-42)-38}{2*5}=\frac{4}{10}
=2/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-42)+38}{2*5}=\frac{80}{10}
=8
$