You have a total of 21 coins, all nickels and dimes. The total value is $1.70. Write and solve a system of equations to find the number of dimes d and the number of nickels n that you have.
I already wrote the equations: n+d=21 and 10d+5n=1.70. But I don't know how to solve it.
1--n+d=21
2--10d+5n=170
3--From (1), d=21-n
4--Substitute into (2) and solve for n and then d.
You have a total of 21 coins, all nickels and dimes. The total value is $1.70. Write and solve a system of equations to find the number of dimes d and the number of nickels n that you have.
I already wrote the equations: n+d=21 and 10d+5n=1.70. But I don't know how to solve it..
2 answers
i get it..thanks!