-23.6=0t+-9.8t^2

Solution for -23.6=0t+-9.8t^2 equation:

-23.6=0t+-9.8t^2

We move all terms to the left:

-23.6-(0t+-9.8t^2)=0

We use the square of the difference formula

-(0t-9.8t^2)-23.6=0

We get rid of parentheses

9.8t^2-0t-23.6=0

We add all the numbers together, and all the variables

9.8t^2-1t-23.6=0

a = 9.8; b = -1; c = -23.6;
Δ = b2-4ac
Δ = -12-4·9.8·(-23.6)
Δ = 926.12
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{926.12}}{2*9.8}=\frac{1-\sqrt{926.12}}{19.6}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+\sqrt{926.12}}{2*9.8}=\frac{1+\sqrt{926.12}}{19.6}
$