Which number sentence is written correctly to have a value of 213 A. 6X4 - 5 = 21
B. 3+ 4 X 3 = 21
C.5 X 4+1 = 21
D. 2 + 5 X 3 = 21

18

step-by-step explanation:

draw the shape and you will see that f and k are actually at adjacent vertices (points of the hexagon that are neighboring).   so find the distance between (1,2) and (4,2).   that is easy since (1,2) and (4,2) is just a vertical distance to count, which is 3.   it is a regular polygon which means all sides are congruent.   you have 6 sides (hexa) so multiply 6 by 3 to receive 18.

here is your mark brainliest

the answer is simply just 6n add the two together as they have an n