How do I an equivalent expression that uses only addition with this?

20-3x - 8y - 4 - 8/7z

Carson has only $20 bills and $10 bill in her wallet. the total value of the bills is $50. she has 1 more $20 bill than $10 bills. how many each kind of bill does carson have? a. one $20 and two $10 bills b. two $20 bills and one $10 bill c. one $20 bills and three $10 bills d. two $20 bills and two $10 bills

Average acceleration: i have no idea how to do this.

Find │7│. a. 1 over 7 b. –7 c. 7 asap i always mark brailiest who me so