Pool Game Angles

Hi can you help me make my player bounce off my walls with a pool game style angles heres the code im using but its not right and i cant solve it myself Player.ScreenPosX +=Player.Speed; Player.ScreenPosY +=Player.Speed; if(Player.ScreenPosX>=750) { Player.Speed = -1; } if(Player.ScreenPosX<=10) { Player.Speed = +1; } if(Player.ScreenPosY>=550) { Player.Speed = -1; } if(Player.ScreenPosY<=10) { Player.Speed = 1; } BltSprite(Player);