Answer:
The variation equation is

Explanation:
From the question, the two masses are

This implies that the product of the two masses

Moreover, the force,f varies directly with the products of the two masses

Also, the force varies inversely with the square of the distance,r

Joining equation 1 and 2, we got


But the constant of variation is k
Multiplying the right hand side of the equation by k, we got
