For heart shape number 1, you will notice that in the second diagram you will see the '*' on the far left side of the arc. That is where you will want to place the center of your compass. This will create the elongated arc.
For heart shape number 2, you will notice that the '*' is located in the middle of the two top arcs. That is where you will place the center of the compass and will create the shortened arc.
Of course, for the final heart, you will just draw straight lines to create the bottom of the heart.
I hope that helps. If not, feel free to contact RSM's help desk at info@rightstartmath.com.