IN THE EXPRESSION Kc=(2X)^2 / (a-x)V , WHY THERE IS A 2 WITH X IN NUMERATOR PLZPLZ HELP ME IN THIS?

(2X)^2 most probably means (in words),that the number in the bracket (in this case 2X) has to be squared so (2X)^2 = 2 times 2 times X times X. Normally this is written 4X^2