One root of x2 +kx – 8 = 0 is square of the other, then, the value of k is-
Options:

2,8,-8,-2

• a,a^2 two roots
  Then a+a^2=-b/a (b=k and a=1 )
  a+a^2=-k (1)
  we also know products of root
  a*a^2=c/a. (c=-8 and a=1)
  a^3=-8
  a=-2. (2)
  Put 2nd in 1st we get
  a+a^2=-k
  -2+(-2)^2=-k
  -2+4=-k
  K=-2. (Ans)
• 5 years agoHelpfull: Yes(0) No(0)
• Let one root be a then another one will be a².
  a+a²=-b÷a=-k
  a*a²=c÷a=_8
  a³=_8=_2
  _2+(-2)²=_k
  K=-2
• 5 years agoHelpfull: Yes(0) No(1)