Answer:
0.8p or p - 0.2p
Step-by-step explanation:
You can find the price for any house minus the down payment by writing an expression with a variable. Let p be the price of the house. If you pay 20% then the price will be lowered by 20%. You will pay as your mortgage 80% of the price. You can write it as either the expression 0.8p or p - 0.2p.
