Let `alpha` and `beta` are the zeroes of `p(x)`.
Then, `alpha+beta = -((-8))/1 = 8`
`alpha beta = k/1 = k`
Now, it is given that ,
`alpha^2+beta^2 = -40`
`=>(alpha+beta)^2-2alpha beta = -40`
`=>8^2-2(k) = =-40`
`=>-2k = -40-64`
`=>2k = 104`
`=>k = 52`