Answer: SSS
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Explanation:
The left slanted side of the smaller triangle is 2 units long. The left slanted side of the larger triangle is 2+2 = 4 units long. The jump from small to large is "times 2".
The same applies when focusing on the right slanted sides for each triangle.
The horizontal pieces also have this same rule applied when going from 4 to 8.
Therefore, the larger triangle's sides are twice as long compared to the smaller triangle's sides.
This is another way of saying that the ratio large/small is equal to 2, and why the SSS similarity theorem works here.
