Can someone answer and explain ill mark brainliest

Answer:
56 of the coins are dimes
Step-by-step explanation:
Dimes = D
Quarters = Q
D+Q=102
10D+25Q=1710
-10(D+Q=102)
-10D-10Q=-1020
+10D+25Q=1710
15Q-690
Q=46
D=102-46=56
CHECK 46(25)+56(10)=1150+560=1710 = YES