If u r asking for the defination then....
triploblastic means body made up of 3 layers of cells. one for inner lining,second for outer lining and third from which differentiated tissues can b made.
bilaterical symmetrical is just like maths "symmetry", it means both left and right part of the orgainism are the ssame..
Triploblastic body is said that the animals whose body develops from three layers--- ectoderm , mesoderm and endoderm of gastrula . Ex: tapeworm. An animal is said to have bilateral symmetry if its body can be divided into two halves by one vertical plane passing through centre. Ex: arthropodes , mollusca and man...etc... pls consider this as a brainliest ans....