math
posted by trixie .
Create a linear system to model this situation. Then use substitution to solve the linear system to solve the problem.
 Bobbie has been saving dimes & quarters to buy a new toy. She has a total of 28 dimes and quarters, with a value of $4.30. How many of each type of coin does Bobbie have?

dimes  x
quarters  28x
10x + 25(28x) = 430
etc