Simplify the following text for a Grade 9 native English-speaking person.
Original: For many years , Sidcup 's Member of Parliament , as part of the Old Bexley and Sidcup constituency was Edward Heath , who was Prime Minister from 1970 to 1974 .
Simplified: For many years , Sidcup had as its constituency ( Old Bexley and Sidcup ) Member of Parliament , the Rt Hon . Sir Edward Heath , Prime Minister 1970-1974 .