Step-by-step explanation:
2 equations with 2 variables.
the most common approach is
1. use one equation to express one variable by the other.
2. use this expression in the second equation and solve for the second variable.
3. use that solution in the original first equation and solve for the first variable.
the end.
0.05N + 0.10D = 2.20
N + D = 23
1. N = 23 - D
2. 0.05(23 - D) + 0.10D = 2.20
1.15 - 0.05D + 0.10D = 2.20
0.05D = 1.05
D = 1.05/0.05 = 21
3. N = 23 - D = 23 - 21 = 2
2 Nickels, 21 Dimes
