"Hi, is your name Ivan?"
Translation:Привет, тебя зовут Иван?
all is right, it has no connection with grammar, but it is important to know Read it here : http://blogs.transparent.com/russian/beyond-%D1%82%D1%8B-and-%D0%B2%D1%8B-formality-in-russian/
У should be dropped in this case. It is used when a person possesses something. Like yu tebya est yabloka, do you have an apple. Apple can be in possession. Your sentence kind of translates to Hi you have a name Ivan? Google translate is not perfect in translation. Some sentences if reverse translated results in different English sentence. So its not reliable.