First you need to find the amount of money the discount decreased.
10(0.2)=2
Then, in order to find the sale price you need to subtract the discount price from the original price of the burger.
10-2=8
Answer: $8
It cost $156.40 because 20% of 195.50 is $39.10 so you subtract that from the 195.50.
Answer:
1. x= -11/3
2. x= 25
hope it helps this is solved by functions