4t=0.4t(t-3.1)=5.8

Solution for 4t=0.4t(t-3.1)=5.8 equation:

4t=0.4t(t-3.1)=5.8

We move all terms to the left:

4t-(0.4t(t-3.1))=0


We calculate terms in parentheses: -(0.4t(t-3.1)), so:

0.4t(t-3.1)

We multiply parentheses

0t^2-0t

We add all the numbers together, and all the variables

t^2-1t

Back to the equation:

-(t^2-1t)


We get rid of parentheses

-t^2+4t+1t=0

We add all the numbers together, and all the variables

-1t^2+5t=0

a = -1; b = 5; c = 0;
Δ = b2-4ac
Δ = 52-4·(-1)·0
Δ = 25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25}=5$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(5)-5}{2*-1}=\frac{-10}{-2}
=+5
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+5}{2*-1}=\frac{0}{-2}
=0
$