0=14t-0.7t^2

Solution for 0=14t-0.7t^2 equation:

0=14t-0.7t^2

We move all terms to the left:

0-(14t-0.7t^2)=0

We add all the numbers together, and all the variables

-(14t-0.7t^2)=0

We get rid of parentheses

0.7t^2-14t=0

a = 0.7; b = -14; c = 0;
Δ = b2-4ac
Δ = -142-4·0.7·0
Δ = 196
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{196}=14$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-14)-14}{2*0.7}=\frac{0}{1.4}
=0
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-14)+14}{2*0.7}=\frac{28}{1.4}
=20
$