5(6.2+z);z=3.6

Solution for 5(6.2+z);z=3.6 equation:

5(6.2+z)z=3.6

We move all terms to the left:

5(6.2+z)z-(3.6)=0

We add all the numbers together, and all the variables

5(z+6.2)z-(3.6)=0

We add all the numbers together, and all the variables

5(z+6.2)z-3.6=0

We multiply parentheses

5z^2+31z-3.6=0

a = 5; b = 31; c = -3.6;
Δ = b2-4ac
Δ = 312-4·5·(-3.6)
Δ = 1033
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$z_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(31)-\sqrt{1033}}{2*5}=\frac{-31-\sqrt{1033}}{10}
$
$z_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(31)+\sqrt{1033}}{2*5}=\frac{-31+\sqrt{1033}}{10}
$