math
posted by Angie .
Bill and Rosa have only nickels and dimes. Rosa has 75 cents and Bill has 90 cents. Each has the same number of coins and Bill has the same number of dimes as Rosa has nickels. How many nickels does Rosa have?

If "each has the same number of coins and Bill has the same number of dimes as Rosa has nickels", then
obviously Bill will have to have the same number of nickels as Rosa has dimes
Bill: number of dimes x , number of nickels y
Roas: number of dimes y , number of nickels x
Bill equation: 10x + 5y = 90
Rosa equation: 10y + 5x = 75
I would double one of them and subtract, easy after that. 
i dnt get ti ...this is so cionfusing

Bill has 7 dimes and 4 nickels
Rosa has 7 nickels and 4 dimes