Answer: 8 dimes and 9 quarters
Step-by-step explanation: In this problem, let's use d to represent number of dimes and q to represent number of quarters.
Since Rodolfo has a total of 17 dimes and quarters, our first equation which is the number equation states that d + q = 17.
Since the total value of Rodolfo's coins is $3.05, our second equation which is the value equation states that 10d + 25q = 305.
Since d represents number of dimes, 10d represents the value of those dimes. In the same way, since q represents number of quarters, 25q represents the value of those quarters.
using the addition method to solve the system from here, you'll find that Rodolfo has 8 dimes and 9 quarters.
I have shown my work for solving the system in the image attached.
