We could write 2 equation based on information above
A = 5-cent coin
B = 10-cent coin
Sum of coin is 8 pcs ==> A + B = 8
Total value of the coin is 65 ==> 5A + 10 B = 65
Solving 2 equation above using substitution
A= 8-B
5(8-B) + 10B = 65
40–5B + 10B = 65
5B = 25 → B= 5
A= 3