Please help due today Prove the sum of two rational numbers is rational where a, b, c, and d are integers and b and d cannot be zero.

the answer is  multiply to get the common denominator my question ask the exact opposite and i already have that answered for me.  

Step-by-step explanation:

point a is the center of the circle that passes through points e, f, and g and the center of the circle that passes through points x, y, and z.