import numpy as np
import pylab as plt

a,b,c = np.meshgrid(np.linspace(-1,1,100), np.linspace(-1,1,100),np.linspace(-1,1,100))

r = a/b + c
#ida = a == b * (r - c)
#idb = b == a / (r - c)
#idc = b == r - a / b