Question

which polygon appears to be regular?
○ figure a
○ figure b
○ figure c
○ figure d
figure a
figure b
figure c
figure d

Explanation:

A regular polygon has all sides equal in length and all interior angles equal in measure.

• Figure A: A rhombus with unequal angles, so not regular.
• Figure B: A trapezoid with unequal sides and angles, so not regular.
• Figure C: An equilateral triangle, which has 3 equal sides and 3 equal interior angles (each $60^\circ$), so it is a regular polygon.
• Figure D: A parallelogram with unequal sides and angles, so not regular.

Answer:

C. Figure C