Question

a triangle does not have a diagonal. which of these figures does not have a diagonal? regular hexagon parallelogram square obtuse triangle

Explanation:

Step1: Recall diagonal definition

A diagonal is a line - segment connecting non - adjacent vertices of a polygon.

Step2: Analyze each option

A regular hexagon has non - adjacent vertices that can be connected by diagonals. A parallelogram has non - adjacent vertices that can be connected by diagonals. A square has non - adjacent vertices that can be connected by diagonals. An obtuse triangle, like any triangle, has no non - adjacent vertices (since all vertices are adjacent to each other), so it has no diagonals.

Answer:

obtuse triangle