<span>6 of them are double 1,1 2,2 3,3 4,4 5,5 6,6
P(doubles)=6/36=1/6</span>
18 is the answer //////////////////
I think answer should be 21
<h2>
Explanation:</h2><h2>
</h2>
Any polygon that has exactly 3 sides is called a triangle. Here you haven't provided any figure, so I'll assume that we have two triangles as indicated in the figure below. As you can see, we have two sides:

When placing together we realize that those sides measures the same, so:

So
is the diagonal of the shape. From the figure we also know that opposite sides are equal and parallel, therefore, this shape represents a parallelogram. Remember that a parallelogram is a quadrilateral where both pairs of opposite sides are parallel.
<em>So correct option is:</em>
<em>Parallelogram</em>