Question

If every pair of equation among the equations $x^{2} +px+qr=0, x^{2} +qx+rp=0, x^{2} +rx+pq=0$ has a common root then the sum of the three common roots is 

Answer 1

the value of 1/p + 1/q + 1/r is -1/2

Answer 2

for kaswa
i think the answer is 455