If sum of the squares of zereos of quadratic polynomial f(x)= x2- 8x+k is 40 . Find the value of k

If sum of the squares of zereos of quadratic polynomial f(x)= x2- 8x+k

1.	If sum of the squares of zereos of quadratic polynomial f(x)= x2- 8x+k is 40 . Find the value of k
Answer» α+β=8αβ=k α^2+β^2=40(α+β)^2-2αβ =408^2-2k=4064 -2k =40-2k =40-64-2k =-24k=12