Tax return question on earn income credit?

i made 29,000 and had a total of 8,000 with held. my wife made 6,000 and had 800 with held. we have one son and my wife and i are going to file jointly. we also qualify for earn income credit, what will our taxe eturn be. no other withholdings or anything like that its straight foward. we dont own a house etheir, just a car . will pick best answer