Step-by-step explanation:
Since, x=8 and x=-5 are the roots.
Therefore, (x - 8) & (x - 5) will be factors.
Hence, required quadratic equation can be given as:
[tex](x - 8)(x - 5) =0 \\ \\ \therefore {x}^{2} + ( - 8 - 5) x+ ( - 8) \times ( - 5) = 0 \\ \\ \therefore {x}^{2} + ( - 13) x+ 40= 0 \\ \\ \huge \red{ \boxed{ \therefore {x}^{2} - 13x+ 40= 0 }} \\ is \: the \: required \: quadratic \: equation.[/tex]
