t=t^2-2.55-13.10

Solution for t=t^2-2.55-13.10 equation:

t=t^2-2.55-13.10

We move all terms to the left:

t-(t^2-2.55-13.10)=0

We get rid of parentheses

-t^2+t+2.55+13.10=0

We add all the numbers together, and all the variables

-1t^2+t+15.65=0

a = -1; b = 1; c = +15.65;
Δ = b2-4ac
Δ = 12-4·(-1)·15.65
Δ = 63.6
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-\sqrt{63.6}}{2*-1}=\frac{-1-\sqrt{63.6}}{-2}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+\sqrt{63.6}}{2*-1}=\frac{-1+\sqrt{63.6}}{-2}
$