7.84 <span> 56% off 14 is equal to (56 x 56) / 100 </span>
Answer:

Step-by-step explanation:
If that is a square, then all sides are the same. Therefore, it's a
by
shape. We'll use Pythagorean Theorem to find the diagonal.

Since it's not a fraction, there is no denominator to rationalize. Let me know if you have any other questions!
It is 75000J
I checked this by plugging in the values above to the kinetic energy formula (1/2mv^2)