Question

A collection of dimes and nickels is worth $9.50. There are 132 coins in all. How many of each coin are there?

Answer 1

number of dimes - x
number of nickels - y

x+y = 132 /*-10 -----> -10x-10y = -1320
10x + 5y = 950

-10x-10y = -1320
10x + 5y = 950
-5y = - 370
y = 74 number of nickels

x+y = 132
x + 74 = 132
x= 132-74
x = 58 number of dimes

Check:
10*58 + 5*74 = 950
950 = 950 True