help with this true or false question

Question

anonymous · Answer

attachment

mathstudent55 · Answer

Correct.

anonymous · Answer

I put true, I just want feedback and also here are some additional questions based on this picture that I was wanting feedback for.

anonymous · Answer

Is it an equilateral, I put true,

anonymous · Answer

Is this figure regular, I put false, because a regular polygon are equiangular and equilateral

mathstudent55 · Answer

Correct again. The small marks across the sides mean all sides are congruent.

anonymous · Answer

Is this figure, concave, I said false,

mathstudent55 · Answer

Correct also about regular.

anonymous · Answer

Is this figure a nonagon... I sad false because this figure has eight sides.

mathstudent55 · Answer

Correct again about nonagon.

anonymous · Answer

yeah! So is the concave one wrong,

anonymous · Answer

SO this figure is concave?

mathstudent55 · Answer

|dw:1406595607904:dw|

anonymous · Answer

Oh okay I get it! Great your awesome!

mathstudent55 · Answer

A concave polygon has at least one interior angle of more than 180 degrees.

mathstudent55 · Answer

|dw:1406595764143:dw|

anonymous · Answer

Yeah I was debating wither that was wrong or right, thanks I thought that was what convex was!!

anonymous · Answer

@mathstudent55 on my question was the answer 12?

mathstudent55 · Answer

The way I remember the difference between concave and convex is that "concave" has the word "cave" in it.
I think of cave as a hole.

anonymous · Answer

Yeah! That's great now ill remember, it thanks again!

mathstudent55 · Answer

You're welcome.