Write a real world situation that could be represented by the system of equations shown below.
y=4x + 10
y=3x + 15

You could say:

y = 4x + 10

John runs 10 miles a week, after every month he adds 4 miles.

y = 3x + 15

Mary runs 15 miles a week, after every month she adds 3 miles.

'y' would represent the total miles and 'x' would represent the number of months.