Answer:
step 2: AA similarity postulate
step 4: proportional
Explanation:
It helps to be familiar with the ways that triangles can be shown to be similar, and what it means when they are.
In general, triangles are similar if their angles have the same measures, and if their sides are proportional. If you know the triangles are not congruent, it is sufficient to know that two of the angles are the same measure.
If the triangles are right triangles, one angle is already known to be 90 degrees in each triangle. All that is needed is to show that one other angle is the same measure. The associated similarity postulate is the "AA similarity postulate" that tells you triangles are similar if two angles have the same measure.
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As we said above, triangles being similar means corresponding sides are proportional.
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In abbreviations like SSS, SAS, ASA, AAS, AA, the letter S stands for Side, and the letter A stands for Angle. The order of the letters corresponds to the order of the sides/angles claimed to be identical.