Kv D Gzc What Substitution Goes In Which? Simple Maths Question..?

What substitution goes in which? Simple maths question..? - kv d gzc

I'm going to GIV, the following question:
A relationship that is used to bring the car stopping distances (d) the ideal way, and if the conditions are as follows:

d = TV + kV (square)

Stirling reaction time was measured at 0.8 seconds. The distance to stop him when the speed was 20 m / s (72km / h), 51-meter run. Putting this information into the formula for determining the value of k.

I know that 51 = 0.8 .. but I do not know what V & V squared () it? It is something like 20 or 72? Need help? 10 points?