Having corresponding sides proportional and corresponding angles equal describes which concept?

Having corresponding sides proportional and corresponding angles equal describes which concept?

• A. Rational
• B. Irrational
• C. Vertical Angles
• D. Similar

Answer: (D)

The concept is similarity in geometry: two shapes are similar when their corresponding angles are equal and their corresponding sides are proportional by a constant scale factor. This matches the description exactly, so the figures have the same shape regardless of size. If the scale factor is 1, they’re congruent (same size and shape). The other terms don't fit: rational and irrational refer to types of numbers, not shapes; vertical angles are equal angles formed by intersecting lines but don’t involve proportional sides.

The concept is similarity in geometry: two shapes are similar when their corresponding angles are equal and their corresponding sides are proportional by a constant scale factor. This matches the description exactly, so the figures have the same shape regardless of size. If the scale factor is 1, they’re congruent (same size and shape). The other terms don't fit: rational and irrational refer to types of numbers, not shapes; vertical angles are equal angles formed by intersecting lines but don’t involve proportional sides.