Marta has opened a savings account with $25. At the end of three months, she has $85 in her account. She deposited the same amount each month during these three months. At what rate has she been making deposits to her savings? $25 a month
$25 a week
$20 a month
$20 a week

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.