Terms of Geometry Crossword

The line that passes through the center of a shape or form.
Any shape with exactly three sides and three angles.
These types of lines intersect to create a right angle.
A triangle that contains a right angle.
Intersecting a system of lines.
A shape with at least three straight sides.
Straight lines passing through a point.
A straight line going from the center of a circle/sphere to the edge of it.
The boundary of a shape (mainly a circle).
A long, narrow mark.
Two angles with a common vertex and side.
An angle that is less than 90 degrees.
A quadrilateral only having on pair of parallel sides.
An angle that is exactly 90 degrees.
Two angles on the inside of the two lines but opposite sides of the transversal.
A small portion of a line.
A rectilinear quadrilateral with opposite sides parallel.
A shape with four equal sides and four right angles.
Identical in form.
A triangle in which all three sides are equal.