Answer:
5x + 10y + 20z = 115
5x + 10y = 75
20z + 75 = 115
Step-by-step explanation:
Given that the wallet contained 11 bills in total
The total value of the bill was $115
The amount of the $5 and $10 was $75
If there was x $5 bills, y $10 bills, and z $20 bill
We have the following equations:
5x + 10y + 20z = 115
5x + 10y = 75
20z + 75 = 115
These are the three equations