Write a system equation to represent this situation

Question

The cost of 8 muffins and 2 quarts of milk is $18. The cost of 3 muffins and 1 quart of milk is $7.50. Write a system of equations to represent this situation. Solve the system of equations by substitution. Explain what the solution means.

Answer 1

Hi Bob, let m represent the muffins and q the milk. Here are the equations:

 

Equation 1:

 

8m + 2q = 18.00

 

Equation 2:

 

3m + q = 7.50

 

Since equation 2 can be written as: q = 7.50 - 3m, this is what I would use for substitution into equation 1.

 

Questions?

Answer 2

8 x muffins + 2 x quart of milk =$18

3 x muffins + 1 x quart of milk =$7.50.

Denote by x muffins and by y quart of milk, then

 8x+2y = 18

 3x+ y  = 7.50

 

Solve it :-)