If sum of the squares of zeros of the quadratic polynomial f(x)=x²+6x-k is 30 the value of k is?

If sum of the squares of zeros of the quadratic polynomial f(x)=x²+6x

1.	If sum of the squares of zeros of the quadratic polynomial f(x)=x²+6x-k is 30 the value of k is?
Answer» Let a and b the zeros then a+b=6 and ab=kGivena squares + b squares=30(a+b)ka whole squares - 2ab=3036-2k=30-2k=30-36-2k=-6K=3