Plz me get the answer asap i been stuck on these

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

How do you solving the solution of each system using elimination?

Aquadratic equation in standard from is written ax^2= bx+c, where a,b and c are real numbers and a is not zero?