what is the area of a kite with a line of 3.16 and 2?
I assume by "line," you are referring to the length of the diagonals. If so, we have
Ak = (1/2)d1d2 where Ak is the area, and d1 and d2 are the lengths of the diagonals
Ak = (1/2)(3.16)(2) = 3.16 sq units