What does a double line inside the walls of a shape mean?

Congruent

Step-by-step explanation:

I think it means they are congruent. Or if you are doing the side and angles I think it represents sides.i hope this helps ☺️

If I remember correctly, It means both of the lines are the same.  

98 points djdjsi zisksis sjsjsi sisksj sksjdj sksks sjsisj

there has been genes found in the x chromosome of males that have been linked to [homo/hetero]sexuality. in addition to the reign of the x chromosome, a section of chromosome 8 has also been link to, "alot of ppl are so " these facts were proven true after a 2014 study of a gay male and his strait brother. according to newscientist.com,"chromosome 14 and is mainly active in the thyroid, but also the brain. called tshr, it makes a type of receptor protein that recognises and binds to a hormone that stimulates the thyroid. in this way, the gene plays an important role in controlling thyroid function. the fact that tshr seems to be involved in sexual orientation fits with evidence that thyroid function seems to be linked to sexuality."

in conclusion, "ppl are so gay" due to their genetics.