Twenty times the square of a non zero number is equal to 20 times the number

Jamie went to home depot.she bought 25 bags of soil that cost $9 per bag.she bought 15 pots at $8 each, and she bought 23 bags of pebbles at $15 each.she used a coupon that gave her $5 off for every 100 dollars she spent. how much did jamie pay at the end?

Ineed with math stuff it involves graphs

Which of the following scenarios demonstrates an exponential decay