Let the number be k
Four times the square of the number is
[tex]4\times k^2[/tex]Twenty times the number is
[tex]20\times k=20k[/tex]Since, four times the square of the number is equal to twenty times the number
It can be illustrated as
[tex]4k^2=20k[/tex]Solving the equation above
[tex]\begin{gathered} 4k^2=20k \\ 4k^2-20k=0 \\ 4k(k-5)=0 \\ \text{Divide both sides by 4k} \\ (k-5)=0 \\ k=5 \\ 4k=0 \\ k=0 \\ k=0\text{ or 5} \end{gathered}[/tex]Hence, the number, k, is 0 or 5
