SOLUTION:
Case: Word problem System of equations)
Method:
Let x be the number of miles they both run
First plan:
Total cost: Initial fee + Cost for total mile driven
y=0 + 0.70x
y= 0.70x
Second plan:
Total cost: Initial fee + Cost for total mile driven
z= 55 + 0.50x
When the costs are equal, y =z
Hence:
0.07x = 55 + 0.50x
0.7x - 0.5x = 55
0.2x = 55

Final answer:
The number of miles Jim needs to drive for the two plans to cost the same is 275 miles