Not including tax, a total of 19 pens and markers cost $11.50. The pens cost $0.25 each, and the markers cost $0.75 each. Write the system of equations that could be used to solve for the number of pens, p, and the number of markers, m, bought.

p + m = ___

p + m = 19

To solve for the number of pens, p, and the number of markers, m, we can create a system of equations based on the given information.

Let's start with the equation for the total number of pens and markers bought:

p + m = 19

Since each pen costs $0.25 and each marker costs $0.75, we can also express the cost of the pens and markers in terms of p and m:

0.25p + 0.75m = 11.50

This equation represents the total cost of pens and markers, which is $11.50.

Thus, the system of equations to solve for the number of pens, p, and the number of markers, m, would be:

p + m = 19
0.25p + 0.75m = 11.50