After doing the last part, where the coordinates are each multiplied by a factor of 10200, fix the program using scaling so that the output is correct for any x,y values.
The scale factor, to prevent overflow when multiplying large numbers, is the larger in absolute value of side_1 or side_2, which should be computed at run-time and stored in a scale variable.
To scale, side_1 and side_2 are divided by the scale factor, and then the computed distance is multiplied by the scale factor.
Note that floating-point absolute value in C is fabs() from math.h, not abs() from stdlib.h which is only for integers.