Final answer:
Two squares with the same side lengths are always congruent. Two rhombuses with the same side lengths are always congruent. Therefore, the true statements are A and C.
Step-by-step explanation:
In this question, we are given different statements about certain shapes and we need to determine which statements are true. Let's go through each option:
A. Two squares with the same side lengths are always congruent. This statement is true. A square is defined by its side length, so if two squares have the same side lengths, they are congruent.
B. Two rectangles with the same side lengths are always congruent. This statement is false. Rectangles can have different dimensions while still having the same side lengths.
C. Two rhombuses with the same side lengths are always congruent. This statement is true. Rhombuses are defined by their side lengths, so two rhombuses with the same side lengths are congruent.
D. Two parallelograms with the same side lengths are always congruent. This statement is false. Parallelograms can have different dimensions while still having the same side lengths.
E. Two quadrilaterals with the same side lengths are always congruent. This statement is false. Quadrilaterals with the same side lengths can have different shapes and dimensions.
Therefore, the true statements are A and C.