Find quartile 1, quartile 2(median) and quartile 3 of the data set {1,1,1,1,2,3,3,4,5,6,6,7,8,8,9,9}. what is the iqr of the data set?

Given: ae ≅ ce ; de ≅ be prove: abcd is a parallelogram. we have that ab || dc. by a similar argument used to prove that △aeb ≅ △ced, we can show that △ ≅ △ceb by. so, ∠cad ≅ ∠ by cpctc. therefore, ad || bc by the converse of the theorem. since both pair of opposite sides are parallel, quadrilateral abcd is a parallelogram.