Full problem in description: She needs to feed 164 cats and 24 dogs. Her budget is $4240. How much can Margie spend on each dog for food and medication?

Question

The full question is: Margie is responsible for buying a week's supply of food and medication for the cats and dogs at a local shelter. The food and medication for each dog costs twice as much as those supplies for a cat. She needs to feed 164 cats and 24 dogs. Her budget is $4240. How much can Margie spend on each dog for food and medication 

I need to set up a matrix and solve it using Cramer's rule. 

Answer 1

The determinant D = (164)(1) - (24)(-2)

 

Dx = (4240)(1) - (24)(0)

 

Dy = (164)(0) - (4240)(-2)

 

Cost for each dog = Dy / D

 

Note: you really don't need to calculate Dx