Two polygons are similar if and only if their corresponding angles are congruent and the measures of their corresponding sides are proportional.

Since , .

By third angle theorem .

Thus, all the corresponding angles are congruent.

Since each triangle is an equilateral triangle, measure of each side of a triangle is same.

Now determine whether corresponding sides are proportional.

Find the ratios of the measures of the corresponding sides.

The ratios of the measures of the corresponding sides are equal, and the

corresponding angles are congruent, so .

The pairs of figures are similar. .

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