In triangle abc segment de is parallel to the side ac . (the endpoints of segment de lie on the sides ab and bc respectively). find de, if ac=20cm, ab=17cm, and bd=11.9cm;
Do one of the following, as appropriate: (a) find the critical value z subscript alpha divided by 2 , (b) find the critical value t subscript alpha divided by 2 . 99%; nequals 17; sigma is unknown; population appears to be normally distributed.