Assets/menu 1.js(10,1): BCE0044: expecting :, found '}'.

how does i solve this problem?
here is the code:

function Update () {
}

function OnGUI () {

if (GUI.Button)(Rect(Screen.width/2,Screen.height/2,90,90,"Começar"));
{
Application.LoadLevel("oi")
}
if (GUI.Button)(Rect(Screen.width/2,Screen.height/2 + 90,90,90,"sair"))
Application.Quit();
}

Your missing a “{” on line 10 and line 6 has a “;” which it shouldnt.