##### Across

**6.**A five-sided polygon.**7.**A ten-sided polygon.**9.**A four-sided polygon.**11.**Two geometric objects having the same measure.**14.**A line that divides a figure in half so that each half is the mirror image of the other.**15.**A three-sided polygon.**16.**An eight-sided polygon.**17.**A straight one-dimensional figure having no thickness and extending infinitely in both directions.**18.**An angle that measures 90ยบ.**19.**Part of a line that starts at a particular point and extends infinitely far in one direction.

##### Down

**1.**A line that intersects a given segment at right angles and divides it into two equal parts.**2.**A segment that connects two nonadjacent vertices of a polygon.**3.**A set of points on a line consisting of two endpoints and all the points between them.**4.**A nine-sided polygon.**5.**A six-sided polygon**8.**A seven-sided polygon.**10.**A common endpoint of two sides of a polygon or an angle.**12.**A series of connected line segments that starts and ends at the same place and does not intersect itself anywhere in between.**13.**The distance around a figure.**14.**A figure formed by two line segments or rays with a common endpoint.