1400=t^2+8t+30

Solution for 1400=t^2+8t+30 equation:

1400=t^2+8t+30

We move all terms to the left:

1400-(t^2+8t+30)=0

We get rid of parentheses

-t^2-8t-30+1400=0

We add all the numbers together, and all the variables

-1t^2-8t+1370=0

a = -1; b = -8; c = +1370;
Δ = b2-4ac
Δ = -82-4·(-1)·1370
Δ = 5544
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{5544}=\sqrt{36*154}=\sqrt{36}*\sqrt{154}=6\sqrt{154}$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-8)-6\sqrt{154}}{2*-1}=\frac{8-6\sqrt{154}}{-2}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-8)+6\sqrt{154}}{2*-1}=\frac{8+6\sqrt{154}}{-2}
$