The harmonic mean of the roots of the equation (5+2)x2−(4+5)x+8+25=0 is

Given equation is  (5+2)x2−(4+5)x+8+25=0Let x1 and x2 are the roots of the equation⇒                 x1+x2=4+55+2………………….(i)and x1x2=8+255+2=2(4+5)5+2=2x1+x2…(ii)∴  Harmonic mean =2x1x2x1+x2=4x1+x2x1+x2=4                                                                  [ from Eq. (ii)]